/*  Prototype JavaScript framework, version 1.6.0
 *  (c) 2005-2007 Sam Stephenson
 *
 *  Prototype is freely distributable under the terms of an MIT-style license.
 *  For details, see the Prototype web site: http://www.prototypejs.org/
 *
 *--------------------------------------------------------------------------*/
var Prototype = Prototype || null;

if(Prototype == null){
	Prototype = {
	  Version: '1.6.0',
	
	  Browser: {
	    IE:     !!(window.attachEvent && !window.opera),
	    Opera:  !!window.opera,
	    WebKit: navigator.userAgent.indexOf('AppleWebKit/') > -1,
	    Gecko:  navigator.userAgent.indexOf('Gecko') > -1 && navigator.userAgent.indexOf('KHTML') == -1,
	    MobileSafari: !!navigator.userAgent.match(/Apple.*Mobile.*Safari/)
	  },
	
	  BrowserFeatures: {
	    XPath: !!document.evaluate,
	    ElementExtensions: !!window.HTMLElement,
	    SpecificElementExtensions:
	      document.createElement('div').__proto__ &&
	      document.createElement('div').__proto__ !==
	        document.createElement('form').__proto__
	  },
	
	  ScriptFragment: '<script[^>]*>([\\S\\s]*?)<\/script>',
	  JSONFilter: /^\/\*-secure-([\s\S]*)\*\/\s*$/,
	
	  emptyFunction: function() { },
	  K: function(x) { return x }
	};
	
	if (Prototype.Browser.MobileSafari)
	  Prototype.BrowserFeatures.SpecificElementExtensions = false;
	
	if (Prototype.Browser.WebKit)
	  Prototype.BrowserFeatures.XPath = false;
	
	/* Based on Alex Arnell's inheritance implementation. */
	var Class = {
	  create: function() {
	    var parent = null, properties = $A(arguments);
	    if (Object.isFunction(properties[0]))
	      parent = properties.shift();
	
	    function klass() {
	      this.initialize.apply(this, arguments);
	    }
	
	    Object.extend(klass, Class.Methods);
	    klass.superclass = parent;
	    klass.subclasses = [];
	
	    if (parent) {
	      var subclass = function() { };
	      subclass.prototype = parent.prototype;
	      klass.prototype = new subclass;
	      parent.subclasses.push(klass);
	    }
	
	    for (var i = 0; i < properties.length; i++)
	      klass.addMethods(properties[i]);
	
	    if (!klass.prototype.initialize)
	      klass.prototype.initialize = Prototype.emptyFunction;
	
	    klass.prototype.constructor = klass;
	
	    return klass;
	  }
	};
	
	Class.Methods = {
	  addMethods: function(source) {
	    var ancestor   = this.superclass && this.superclass.prototype;
	    var properties = Object.keys(source);
	
	    if (!Object.keys({ toString: true }).length)
	      properties.push("toString", "valueOf");
	
	    for (var i = 0, length = properties.length; i < length; i++) {
	      var property = properties[i], value = source[property];
	      if (ancestor && Object.isFunction(value) &&
	          value.argumentNames().first() == "$super") {
	        var method = value, value = Object.extend((function(m) {
	          return function() { return ancestor[m].apply(this, arguments) };
	        })(property).wrap(method), {
	          valueOf:  function() { return method },
	          toString: function() { return method.toString() }
	        });
	      }
	      this.prototype[property] = value;
	    }
	
	    return this;
	  }
	};
	
	var Abstract = { };
	
	Object.extend = function(destination, source) {
	  for (var property in source)
	    destination[property] = source[property];
	  return destination;
	};
	
	Object.extend(Object, {
	  inspect: function(object) {
	    try {
	      if (object === undefined) return 'undefined';
	      if (object === null) return 'null';
	      return object.inspect ? object.inspect() : object.toString();
	    } catch (e) {
	      if (e instanceof RangeError) return '...';
	      throw e;
	    }
	  },
	
	  toJSON: function(object) {
	    var type = typeof object;
	    switch (type) {
	      case 'undefined':
	      case 'function':
	      case 'unknown': return;
	      case 'boolean': return object.toString();
	    }
	
	    if (object === null) return 'null';
	    if (object.toJSON) return object.toJSON();
	    if (Object.isElement(object)) return;
	
	    var results = [];
	    for (var property in object) {
	      var value = Object.toJSON(object[property]);
	      if (value !== undefined)
	        results.push(property.toJSON() + ': ' + value);
	    }
	
	    return '{' + results.join(', ') + '}';
	  },
	
	  toQueryString: function(object) {
	    return $H(object).toQueryString();
	  },
	
	  toHTML: function(object) {
	    return object && object.toHTML ? object.toHTML() : String.interpret(object);
	  },
	
	  keys: function(object) {
	    var keys = [];
	    for (var property in object)
	      keys.push(property);
	    return keys;
	  },
	
	  values: function(object) {
	    var values = [];
	    for (var property in object)
	      values.push(object[property]);
	    return values;
	  },
	
	  clone: function(object) {
	    return Object.extend({ }, object);
	  },
	
	  isElement: function(object) {
	    return object && object.nodeType == 1;
	  },
	
	  isArray: function(object) {
	    return object && object.constructor === Array;
	  },
	
	  isHash: function(object) {
	    return object instanceof Hash;
	  },
	
	  isFunction: function(object) {
	    return typeof object == "function";
	  },
	
	  isString: function(object) {
	    return typeof object == "string";
	  },
	
	  isNumber: function(object) {
	    return typeof object == "number";
	  },
	
	  isUndefined: function(object) {
	    return typeof object == "undefined";
	  }
	});
	
	Object.extend(Function.prototype, {
	  argumentNames: function() {
	    var names = this.toString().match(/^[\s\(]*function[^(]*\((.*?)\)/)[1].split(",").invoke("strip");
	    return names.length == 1 && !names[0] ? [] : names;
	  },
	
	  bind: function() {
	    if (arguments.length < 2 && arguments[0] === undefined) return this;
	    var __method = this, args = $A(arguments), object = args.shift();
	    return function() {
	      return __method.apply(object, args.concat($A(arguments)));
	    }
	  },
	
	  bindAsEventListener: function() {
	    var __method = this, args = $A(arguments), object = args.shift();
	    return function(event) {
	      return __method.apply(object, [event || window.event].concat(args));
	    }
	  },
	
	  curry: function() {
	    if (!arguments.length) return this;
	    var __method = this, args = $A(arguments);
	    return function() {
	      return __method.apply(this, args.concat($A(arguments)));
	    }
	  },
	
	  delay: function() {
	    var __method = this, args = $A(arguments), timeout = args.shift() * 1000;
	    return window.setTimeout(function() {
	      return __method.apply(__method, args);
	    }, timeout);
	  },
	
	  wrap: function(wrapper) {
	    var __method = this;
	    return function() {
	      return wrapper.apply(this, [__method.bind(this)].concat($A(arguments)));
	    }
	  },
	
	  methodize: function() {
	    if (this._methodized) return this._methodized;
	    var __method = this;
	    return this._methodized = function() {
	      return __method.apply(null, [this].concat($A(arguments)));
	    };
	  }
	});
	
	Function.prototype.defer = Function.prototype.delay.curry(0.01);
	
	Date.prototype.toJSON = function() {
	  return '"' + this.getUTCFullYear() + '-' +
	    (this.getUTCMonth() + 1).toPaddedString(2) + '-' +
	    this.getUTCDate().toPaddedString(2) + 'T' +
	    this.getUTCHours().toPaddedString(2) + ':' +
	    this.getUTCMinutes().toPaddedString(2) + ':' +
	    this.getUTCSeconds().toPaddedString(2) + 'Z"';
	};
	
	var Try = {
	  these: function() {
	    var returnValue;
	
	    for (var i = 0, length = arguments.length; i < length; i++) {
	      var lambda = arguments[i];
	      try {
	        returnValue = lambda();
	        break;
	      } catch (e) { }
	    }
	
	    return returnValue;
	  }
	};
	
	RegExp.prototype.match = RegExp.prototype.test;
	
	RegExp.escape = function(str) {
	  return String(str).replace(/([.*+?^=!:${}()|[\]\/\\])/g, '\\$1');
	};
	
	/*--------------------------------------------------------------------------*/
	
	var PeriodicalExecuter = Class.create({
	  initialize: function(callback, frequency) {
	    this.callback = callback;
	    this.frequency = frequency;
	    this.currentlyExecuting = false;
	
	    this.registerCallback();
	  },
	
	  registerCallback: function() {
	    this.timer = setInterval(this.onTimerEvent.bind(this), this.frequency * 1000);
	  },
	
	  execute: function() {
	    this.callback(this);
	  },
	
	  stop: function() {
	    if (!this.timer) return;
	    clearInterval(this.timer);
	    this.timer = null;
	  },
	
	  onTimerEvent: function() {
	    if (!this.currentlyExecuting) {
	      try {
	        this.currentlyExecuting = true;
	        this.execute();
	      } finally {
	        this.currentlyExecuting = false;
	      }
	    }
	  }
	});
	Object.extend(String, {
	  interpret: function(value) {
	    return value == null ? '' : String(value);
	  },
	  specialChar: {
	    '\b': '\\b',
	    '\t': '\\t',
	    '\n': '\\n',
	    '\f': '\\f',
	    '\r': '\\r',
	    '\\': '\\\\'
	  }
	});
	
	Object.extend(String.prototype, {
	  gsub: function(pattern, replacement) {
	    var result = '', source = this, match;
	    replacement = arguments.callee.prepareReplacement(replacement);
	
	    while (source.length > 0) {
	      if (match = source.match(pattern)) {
	        result += source.slice(0, match.index);
	        result += String.interpret(replacement(match));
	        source  = source.slice(match.index + match[0].length);
	      } else {
	        result += source, source = '';
	      }
	    }
	    return result;
	  },
	
	  sub: function(pattern, replacement, count) {
	    replacement = this.gsub.prepareReplacement(replacement);
	    count = count === undefined ? 1 : count;
	
	    return this.gsub(pattern, function(match) {
	      if (--count < 0) return match[0];
	      return replacement(match);
	    });
	  },
	
	  scan: function(pattern, iterator) {
	    this.gsub(pattern, iterator);
	    return String(this);
	  },
	
	  truncate: function(length, truncation) {
	    length = length || 30;
	    truncation = truncation === undefined ? '...' : truncation;
	    return this.length > length ?
	      this.slice(0, length - truncation.length) + truncation : String(this);
	  },
	
	  strip: function() {
	    return this.replace(/^\s+/, '').replace(/\s+$/, '');
	  },
	
	  stripTags: function() {
	    return this.replace(/<\/?[^>]+>/gi, '');
	  },
	
	  stripScripts: function() {
	    return this.replace(new RegExp(Prototype.ScriptFragment, 'img'), '');
	  },
	
	  extractScripts: function() {
	    var matchAll = new RegExp(Prototype.ScriptFragment, 'img');
	    var matchOne = new RegExp(Prototype.ScriptFragment, 'im');
	    return (this.match(matchAll) || []).map(function(scriptTag) {
	      return (scriptTag.match(matchOne) || ['', ''])[1];
	    });
	  },
	
	  evalScripts: function() {
	    return this.extractScripts().map(function(script) { return eval(script) });
	  },
	
	  escapeHTML: function() {
	    var self = arguments.callee;
	    self.text.data = this;
	    return self.div.innerHTML;
	  },
	
	  unescapeHTML: function() {
	    var div = new Element('div');
	    div.innerHTML = this.stripTags();
	    return div.childNodes[0] ? (div.childNodes.length > 1 ?
	      $A(div.childNodes).inject('', function(memo, node) { return memo+node.nodeValue }) :
	      div.childNodes[0].nodeValue) : '';
	  },
	
	  toQueryParams: function(separator) {
	    var match = this.strip().match(/([^?#]*)(#.*)?$/);
	    if (!match) return { };
	
	    return match[1].split(separator || '&').inject({ }, function(hash, pair) {
	      if ((pair = pair.split('='))[0]) {
	        var key = decodeURIComponent(pair.shift());
	        var value = pair.length > 1 ? pair.join('=') : pair[0];
	        if (value != undefined) value = decodeURIComponent(value);
	
	        if (key in hash) {
	          if (!Object.isArray(hash[key])) hash[key] = [hash[key]];
	          hash[key].push(value);
	        }
	        else hash[key] = value;
	      }
	      return hash;
	    });
	  },
	
	  toArray: function() {
	    return this.split('');
	  },
	
	  succ: function() {
	    return this.slice(0, this.length - 1) +
	      String.fromCharCode(this.charCodeAt(this.length - 1) + 1);
	  },
	
	  times: function(count) {
	    return count < 1 ? '' : new Array(count + 1).join(this);
	  },
	
	  camelize: function() {
	    var parts = this.split('-'), len = parts.length;
	    if (len == 1) return parts[0];
	
	    var camelized = this.charAt(0) == '-'
	      ? parts[0].charAt(0).toUpperCase() + parts[0].substring(1)
	      : parts[0];
	
	    for (var i = 1; i < len; i++)
	      camelized += parts[i].charAt(0).toUpperCase() + parts[i].substring(1);
	
	    return camelized;
	  },
	
	  capitalize: function() {
	    return this.charAt(0).toUpperCase() + this.substring(1).toLowerCase();
	  },
	
	  underscore: function() {
	    return this.gsub(/::/, '/').gsub(/([A-Z]+)([A-Z][a-z])/,'#{1}_#{2}').gsub(/([a-z\d])([A-Z])/,'#{1}_#{2}').gsub(/-/,'_').toLowerCase();
	  },
	
	  dasherize: function() {
	    return this.gsub(/_/,'-');
	  },
	
	  inspect: function(useDoubleQuotes) {
	    var escapedString = this.gsub(/[\x00-\x1f\\]/, function(match) {
	      var character = String.specialChar[match[0]];
	      return character ? character : '\\u00' + match[0].charCodeAt().toPaddedString(2, 16);
	    });
	    if (useDoubleQuotes) return '"' + escapedString.replace(/"/g, '\\"') + '"';
	    return "'" + escapedString.replace(/'/g, '\\\'') + "'";
	  },
	
	  toJSON: function() {
	    return this.inspect(true);
	  },
	
	  unfilterJSON: function(filter) {
	    return this.sub(filter || Prototype.JSONFilter, '#{1}');
	  },
	
	  isJSON: function() {
	    var str = this.replace(/\\./g, '@').replace(/"[^"\\\n\r]*"/g, '');
	    return (/^[,:{}\[\]0-9.\-+Eaeflnr-u \n\r\t]*$/).test(str);
	  },
	
	  evalJSON: function(sanitize) {
	    var json = this.unfilterJSON();
	    try {
	      if (!sanitize || json.isJSON()) return eval('(' + json + ')');
	    } catch (e) { }
	    throw new SyntaxError('Badly formed JSON string: ' + this.inspect());
	  },
	
	  include: function(pattern) {
	    return this.indexOf(pattern) > -1;
	  },
	
	  startsWith: function(pattern) {
	    return this.indexOf(pattern) === 0;
	  },
	
	  endsWith: function(pattern) {
	    var d = this.length - pattern.length;
	    return d >= 0 && this.lastIndexOf(pattern) === d;
	  },
	
	  empty: function() {
	    return this == '';
	  },
	
	  blank: function() {
	    return /^\s*$/.test(this);
	  },
	
	  interpolate: function(object, pattern) {
	    return new Template(this, pattern).evaluate(object);
	  }
	});
	
	if (Prototype.Browser.WebKit || Prototype.Browser.IE) Object.extend(String.prototype, {
	  escapeHTML: function() {
	    return this.replace(/&/g,'&amp;').replace(/</g,'&lt;').replace(/>/g,'&gt;');
	  },
	  unescapeHTML: function() {
	    return this.replace(/&amp;/g,'&').replace(/&lt;/g,'<').replace(/&gt;/g,'>');
	  }
	});
	
	String.prototype.gsub.prepareReplacement = function(replacement) {
	  if (Object.isFunction(replacement)) return replacement;
	  var template = new Template(replacement);
	  return function(match) { return template.evaluate(match) };
	};
	
	String.prototype.parseQuery = String.prototype.toQueryParams;
	
	Object.extend(String.prototype.escapeHTML, {
	  div:  document.createElement('div'),
	  text: document.createTextNode('')
	});
	
	with (String.prototype.escapeHTML) div.appendChild(text);
	
	var Template = Class.create({
	  initialize: function(template, pattern) {
	    this.template = template.toString();
	    this.pattern = pattern || Template.Pattern;
	  },
	
	  evaluate: function(object) {
	    if (Object.isFunction(object.toTemplateReplacements))
	      object = object.toTemplateReplacements();
	
	    return this.template.gsub(this.pattern, function(match) {
	      if (object == null) return '';
	
	      var before = match[1] || '';
	      if (before == '\\') return match[2];
	
	      var ctx = object, expr = match[3];
	      var pattern = /^([^.[]+|\[((?:.*?[^\\])?)\])(\.|\[|$)/, match = pattern.exec(expr);
	      if (match == null) return before;
	
	      while (match != null) {
	        var comp = match[1].startsWith('[') ? match[2].gsub('\\\\]', ']') : match[1];
	        ctx = ctx[comp];
	        if (null == ctx || '' == match[3]) break;
	        expr = expr.substring('[' == match[3] ? match[1].length : match[0].length);
	        match = pattern.exec(expr);
	      }
	
	      return before + String.interpret(ctx);
	    }.bind(this));
	  }
	});
	Template.Pattern = /(^|.|\r|\n)(#\{(.*?)\})/;
	
	var $break = { };
	
	var Enumerable = {
	  each: function(iterator, context) {
	    var index = 0;
	    iterator = iterator.bind(context);
	    try {
	      this._each(function(value) {
	        iterator(value, index++);
	      });
	    } catch (e) {
	      if (e != $break) throw e;
	    }
	    return this;
	  },
	
	  eachSlice: function(number, iterator, context) {
	    iterator = iterator ? iterator.bind(context) : Prototype.K;
	    var index = -number, slices = [], array = this.toArray();
	    while ((index += number) < array.length)
	      slices.push(array.slice(index, index+number));
	    return slices.collect(iterator, context);
	  },
	
	  all: function(iterator, context) {
	    iterator = iterator ? iterator.bind(context) : Prototype.K;
	    var result = true;
	    this.each(function(value, index) {
	      result = result && !!iterator(value, index);
	      if (!result) throw $break;
	    });
	    return result;
	  },
	
	  any: function(iterator, context) {
	    iterator = iterator ? iterator.bind(context) : Prototype.K;
	    var result = false;
	    this.each(function(value, index) {
	      if (result = !!iterator(value, index))
	        throw $break;
	    });
	    return result;
	  },
	
	  collect: function(iterator, context) {
	    iterator = iterator ? iterator.bind(context) : Prototype.K;
	    var results = [];
	    this.each(function(value, index) {
	      results.push(iterator(value, index));
	    });
	    return results;
	  },
	
	  detect: function(iterator, context) {
	    iterator = iterator.bind(context);
	    var result;
	    this.each(function(value, index) {
	      if (iterator(value, index)) {
	        result = value;
	        throw $break;
	      }
	    });
	    return result;
	  },
	
	  findAll: function(iterator, context) {
	    iterator = iterator.bind(context);
	    var results = [];
	    this.each(function(value, index) {
	      if (iterator(value, index))
	        results.push(value);
	    });
	    return results;
	  },
	
	  grep: function(filter, iterator, context) {
	    iterator = iterator ? iterator.bind(context) : Prototype.K;
	    var results = [];
	
	    if (Object.isString(filter))
	      filter = new RegExp(filter);
	
	    this.each(function(value, index) {
	      if (filter.match(value))
	        results.push(iterator(value, index));
	    });
	    return results;
	  },
	
	  include: function(object) {
	    if (Object.isFunction(this.indexOf))
	      if (this.indexOf(object) != -1) return true;
	
	    var found = false;
	    this.each(function(value) {
	      if (value == object) {
	        found = true;
	        throw $break;
	      }
	    });
	    return found;
	  },
	
	  inGroupsOf: function(number, fillWith) {
	    fillWith = fillWith === undefined ? null : fillWith;
	    return this.eachSlice(number, function(slice) {
	      while(slice.length < number) slice.push(fillWith);
	      return slice;
	    });
	  },
	
	  inject: function(memo, iterator, context) {
	    iterator = iterator.bind(context);
	    this.each(function(value, index) {
	      memo = iterator(memo, value, index);
	    });
	    return memo;
	  },
	
	  invoke: function(method) {
	    var args = $A(arguments).slice(1);
	    return this.map(function(value) {
	      return value[method].apply(value, args);
	    });
	  },
	
	  max: function(iterator, context) {
	    iterator = iterator ? iterator.bind(context) : Prototype.K;
	    var result;
	    this.each(function(value, index) {
	      value = iterator(value, index);
	      if (result == undefined || value >= result)
	        result = value;
	    });
	    return result;
	  },
	
	  min: function(iterator, context) {
	    iterator = iterator ? iterator.bind(context) : Prototype.K;
	    var result;
	    this.each(function(value, index) {
	      value = iterator(value, index);
	      if (result == undefined || value < result)
	        result = value;
	    });
	    return result;
	  },
	
	  partition: function(iterator, context) {
	    iterator = iterator ? iterator.bind(context) : Prototype.K;
	    var trues = [], falses = [];
	    this.each(function(value, index) {
	      (iterator(value, index) ?
	        trues : falses).push(value);
	    });
	    return [trues, falses];
	  },
	
	  pluck: function(property) {
	    var results = [];
	    this.each(function(value) {
	      results.push(value[property]);
	    });
	    return results;
	  },
	
	  reject: function(iterator, context) {
	    iterator = iterator.bind(context);
	    var results = [];
	    this.each(function(value, index) {
	      if (!iterator(value, index))
	        results.push(value);
	    });
	    return results;
	  },
	
	  sortBy: function(iterator, context) {
	    iterator = iterator.bind(context);
	    return this.map(function(value, index) {
	      return {value: value, criteria: iterator(value, index)};
	    }).sort(function(left, right) {
	      var a = left.criteria, b = right.criteria;
	      return a < b ? -1 : a > b ? 1 : 0;
	    }).pluck('value');
	  },
	
	  toArray: function() {
	    return this.map();
	  },
	
	  zip: function() {
	    var iterator = Prototype.K, args = $A(arguments);
	    if (Object.isFunction(args.last()))
	      iterator = args.pop();
	
	    var collections = [this].concat(args).map($A);
	    return this.map(function(value, index) {
	      return iterator(collections.pluck(index));
	    });
	  },
	
	  size: function() {
	    return this.toArray().length;
	  },
	
	  inspect: function() {
	    return '#<Enumerable:' + this.toArray().inspect() + '>';
	  }
	};
	
	Object.extend(Enumerable, {
	  map:     Enumerable.collect,
	  find:    Enumerable.detect,
	  select:  Enumerable.findAll,
	  filter:  Enumerable.findAll,
	  member:  Enumerable.include,
	  entries: Enumerable.toArray,
	  every:   Enumerable.all,
	  some:    Enumerable.any
	});
	function $A(iterable) {
	  if (!iterable) return [];
	  if (iterable.toArray) return iterable.toArray();
	  var length = iterable.length, results = new Array(length);
	  while (length--) results[length] = iterable[length];
	  return results;
	}
	
	if (Prototype.Browser.WebKit) {
	  function $A(iterable) {
	    if (!iterable) return [];
	    if (!(Object.isFunction(iterable) && iterable == '[object NodeList]') &&
	        iterable.toArray) return iterable.toArray();
	    var length = iterable.length, results = new Array(length);
	    while (length--) results[length] = iterable[length];
	    return results;
	  }
	}
	
	Array.from = $A;
	
	Object.extend(Array.prototype, Enumerable);
	
	if (!Array.prototype._reverse) Array.prototype._reverse = Array.prototype.reverse;
	
	Object.extend(Array.prototype, {
	  _each: function(iterator) {
	    for (var i = 0, length = this.length; i < length; i++)
	      iterator(this[i]);
	  },
	
	  clear: function() {
	    this.length = 0;
	    return this;
	  },
	
	  first: function() {
	    return this[0];
	  },
	
	  last: function() {
	    return this[this.length - 1];
	  },
	
	  compact: function() {
	    return this.select(function(value) {
	      return value != null;
	    });
	  },
	
	  flatten: function() {
	    return this.inject([], function(array, value) {
	      return array.concat(Object.isArray(value) ?
	        value.flatten() : [value]);
	    });
	  },
	
	  without: function() {
	    var values = $A(arguments);
	    return this.select(function(value) {
	      return !values.include(value);
	    });
	  },
	
	  reverse: function(inline) {
	    return (inline !== false ? this : this.toArray())._reverse();
	  },
	
	  reduce: function() {
	    return this.length > 1 ? this : this[0];
	  },
	
	  uniq: function(sorted) {
	    return this.inject([], function(array, value, index) {
	      if (0 == index || (sorted ? array.last() != value : !array.include(value)))
	        array.push(value);
	      return array;
	    });
	  },
	
	  intersect: function(array) {
	    return this.uniq().findAll(function(item) {
	      return array.detect(function(value) { return item === value });
	    });
	  },
	
	  clone: function() {
	    return [].concat(this);
	  },
	
	  size: function() {
	    return this.length;
	  },
	
	  inspect: function() {
	    return '[' + this.map(Object.inspect).join(', ') + ']';
	  },
	
	  toJSON: function() {
	    var results = [];
	    this.each(function(object) {
	      var value = Object.toJSON(object);
	      if (value !== undefined) results.push(value);
	    });
	    return '[' + results.join(', ') + ']';
	  }
	});
	
	// use native browser JS 1.6 implementation if available
	if (Object.isFunction(Array.prototype.forEach))
	  Array.prototype._each = Array.prototype.forEach;
	
	if (!Array.prototype.indexOf) Array.prototype.indexOf = function(item, i) {
	  i || (i = 0);
	  var length = this.length;
	  if (i < 0) i = length + i;
	  for (; i < length; i++)
	    if (this[i] === item) return i;
	  return -1;
	};
	
	if (!Array.prototype.lastIndexOf) Array.prototype.lastIndexOf = function(item, i) {
	  i = isNaN(i) ? this.length : (i < 0 ? this.length + i : i) + 1;
	  var n = this.slice(0, i).reverse().indexOf(item);
	  return (n < 0) ? n : i - n - 1;
	};
	
	Array.prototype.toArray = Array.prototype.clone;
	
	function $w(string) {
	  if (!Object.isString(string)) return [];
	  string = string.strip();
	  return string ? string.split(/\s+/) : [];
	}
	
	if (Prototype.Browser.Opera){
	  Array.prototype.concat = function() {
	    var array = [];
	    for (var i = 0, length = this.length; i < length; i++) array.push(this[i]);
	    for (var i = 0, length = arguments.length; i < length; i++) {
	      if (Object.isArray(arguments[i])) {
	        for (var j = 0, arrayLength = arguments[i].length; j < arrayLength; j++)
	          array.push(arguments[i][j]);
	      } else {
	        array.push(arguments[i]);
	      }
	    }
	    return array;
	  };
	}
	Object.extend(Number.prototype, {
	  toColorPart: function() {
	    return this.toPaddedString(2, 16);
	  },
	
	  succ: function() {
	    return this + 1;
	  },
	
	  times: function(iterator) {
	    $R(0, this, true).each(iterator);
	    return this;
	  },
	
	  toPaddedString: function(length, radix) {
	    var string = this.toString(radix || 10);
	    return '0'.times(length - string.length) + string;
	  },
	
	  toJSON: function() {
	    return isFinite(this) ? this.toString() : 'null';
	  }
	});
	
	$w('abs round ceil floor').each(function(method){
	  Number.prototype[method] = Math[method].methodize();
	});
	function $H(object) {
	  return new Hash(object);
	};
	
	var Hash = Class.create(Enumerable, (function() {
	  if (function() {
	    var i = 0, Test = function(value) { this.key = value };
	    Test.prototype.key = 'foo';
	    for (var property in new Test('bar')) i++;
	    return i > 1;
	  }()) {
	    function each(iterator) {
	      var cache = [];
	      for (var key in this._object) {
	        var value = this._object[key];
	        if (cache.include(key)) continue;
	        cache.push(key);
	        var pair = [key, value];
	        pair.key = key;
	        pair.value = value;
	        iterator(pair);
	      }
	    }
	  } else {
	    function each(iterator) {
	      for (var key in this._object) {
	        var value = this._object[key], pair = [key, value];
	        pair.key = key;
	        pair.value = value;
	        iterator(pair);
	      }
	    }
	  }
	
	  function toQueryPair(key, value) {
	    if (Object.isUndefined(value)) return key;
	    return key + '=' + encodeURIComponent(String.interpret(value));
	  }
	
	  return {
	    initialize: function(object) {
	      this._object = Object.isHash(object) ? object.toObject() : Object.clone(object);
	    },
	
	    _each: each,
	
	    set: function(key, value) {
	      return this._object[key] = value;
	    },
	
	    get: function(key) {
	      return this._object[key];
	    },
	
	    unset: function(key) {
	      var value = this._object[key];
	      delete this._object[key];
	      return value;
	    },
	
	    toObject: function() {
	      return Object.clone(this._object);
	    },
	
	    keys: function() {
	      return this.pluck('key');
	    },
	
	    values: function() {
	      return this.pluck('value');
	    },
	
	    index: function(value) {
	      var match = this.detect(function(pair) {
	        return pair.value === value;
	      });
	      return match && match.key;
	    },
	
	    merge: function(object) {
	      return this.clone().update(object);
	    },
	
	    update: function(object) {
	      return new Hash(object).inject(this, function(result, pair) {
	        result.set(pair.key, pair.value);
	        return result;
	      });
	    },
	
	    toQueryString: function() {
	      return this.map(function(pair) {
	        var key = encodeURIComponent(pair.key), values = pair.value;
	
	        if (values && typeof values == 'object') {
	          if (Object.isArray(values))
	            return values.map(toQueryPair.curry(key)).join('&');
	        }
	        return toQueryPair(key, values);
	      }).join('&');
	    },
	
	    inspect: function() {
	      return '#<Hash:{' + this.map(function(pair) {
	        return pair.map(Object.inspect).join(': ');
	      }).join(', ') + '}>';
	    },
	
	    toJSON: function() {
	      return Object.toJSON(this.toObject());
	    },
	
	    clone: function() {
	      return new Hash(this);
	    }
	  }
	})());
	
	Hash.prototype.toTemplateReplacements = Hash.prototype.toObject;
	Hash.from = $H;
	var ObjectRange = Class.create(Enumerable, {
	  initialize: function(start, end, exclusive) {
	    this.start = start;
	    this.end = end;
	    this.exclusive = exclusive;
	  },
	
	  _each: function(iterator) {
	    var value = this.start;
	    while (this.include(value)) {
	      iterator(value);
	      value = value.succ();
	    }
	  },
	
	  include: function(value) {
	    if (value < this.start)
	      return false;
	    if (this.exclusive)
	      return value < this.end;
	    return value <= this.end;
	  }
	});
	
	var $R = function(start, end, exclusive) {
	  return new ObjectRange(start, end, exclusive);
	};
	
	var Ajax = {
	  getTransport: function() {
	    return Try.these(
	      function() {return new XMLHttpRequest()},
	      function() {return new ActiveXObject('Msxml2.XMLHTTP')},
	      function() {return new ActiveXObject('Microsoft.XMLHTTP')}
	    ) || false;
	  },
	
	  activeRequestCount: 0
	};
	
	Ajax.Responders = {
	  responders: [],
	
	  _each: function(iterator) {
	    this.responders._each(iterator);
	  },
	
	  register: function(responder) {
	    if (!this.include(responder))
	      this.responders.push(responder);
	  },
	
	  unregister: function(responder) {
	    this.responders = this.responders.without(responder);
	  },
	
	  dispatch: function(callback, request, transport, json) {
	    this.each(function(responder) {
	      if (Object.isFunction(responder[callback])) {
	        try {
	          responder[callback].apply(responder, [request, transport, json]);
	        } catch (e) { }
	      }
	    });
	  }
	};
	
	Object.extend(Ajax.Responders, Enumerable);
	
	Ajax.Responders.register({
	  onCreate:   function() { Ajax.activeRequestCount++ },
	  onComplete: function() { Ajax.activeRequestCount-- }
	});
	
	Ajax.Base = Class.create({
	  initialize: function(options) {
	    this.options = {
	      method:       'post',
	      asynchronous: true,
	      contentType:  'application/x-www-form-urlencoded',
	      encoding:     'UTF-8',
	      parameters:   '',
	      evalJSON:     true,
	      evalJS:       true
	    };
	    Object.extend(this.options, options || { });
	
	    this.options.method = this.options.method.toLowerCase();
	    if (Object.isString(this.options.parameters))
	      this.options.parameters = this.options.parameters.toQueryParams();
	  }
	});
	
	Ajax.Request = Class.create(Ajax.Base, {
	  _complete: false,
	
	  initialize: function($super, url, options) {
	    $super(options);
	    this.transport = Ajax.getTransport();
	    this.request(url);
	  },
	
	  request: function(url) {
	    this.url = url;
	    this.method = this.options.method;
	    var params = Object.clone(this.options.parameters);
	
	    if (!['get', 'post'].include(this.method)) {
	      // simulate other verbs over post
	      params['_method'] = this.method;
	      this.method = 'post';
	    }
	
	    this.parameters = params;
	
	    if (params = Object.toQueryString(params)) {
	      // when GET, append parameters to URL
	      if (this.method == 'get')
	        this.url += (this.url.include('?') ? '&' : '?') + params;
	      else if (/Konqueror|Safari|KHTML/.test(navigator.userAgent))
	        params += '&_=';
	    }
	
	    try {
	      var response = new Ajax.Response(this);
	      if (this.options.onCreate) this.options.onCreate(response);
	      Ajax.Responders.dispatch('onCreate', this, response);
	
	      this.transport.open(this.method.toUpperCase(), this.url,
	        this.options.asynchronous);
	
	      if (this.options.asynchronous) this.respondToReadyState.bind(this).defer(1);
	
	      this.transport.onreadystatechange = this.onStateChange.bind(this);
	      this.setRequestHeaders();
	
	      this.body = this.method == 'post' ? (this.options.postBody || params) : null;
	      this.transport.send(this.body);
	
	      /* Force Firefox to handle ready state 4 for synchronous requests */
	      if (!this.options.asynchronous && this.transport.overrideMimeType)
	        this.onStateChange();
	
	    }
	    catch (e) {
	      this.dispatchException(e);
	    }
	  },
	
	  onStateChange: function() {
	    var readyState = this.transport.readyState;
	    if (readyState > 1 && !((readyState == 4) && this._complete))
	      this.respondToReadyState(this.transport.readyState);
	  },
	
	  setRequestHeaders: function() {
	    var headers = {
	      'X-Requested-With': 'XMLHttpRequest',
	      'X-Prototype-Version': Prototype.Version,
	      'Accept': 'text/javascript, text/html, application/xml, text/xml, */*'
	    };
	
	    if (this.method == 'post') {
	      headers['Content-type'] = this.options.contentType +
	        (this.options.encoding ? '; charset=' + this.options.encoding : '');
	
	      /* Force "Connection: close" for older Mozilla browsers to work
	       * around a bug where XMLHttpRequest sends an incorrect
	       * Content-length header. See Mozilla Bugzilla #246651.
	       */
	      if (this.transport.overrideMimeType &&
	          (navigator.userAgent.match(/Gecko\/(\d{4})/) || [0,2005])[1] < 2005)
	            headers['Connection'] = 'close';
	    }
	
	    // user-defined headers
	    if (typeof this.options.requestHeaders == 'object') {
	      var extras = this.options.requestHeaders;
	
	      if (Object.isFunction(extras.push))
	        for (var i = 0, length = extras.length; i < length; i += 2)
	          headers[extras[i]] = extras[i+1];
	      else
	        $H(extras).each(function(pair) { headers[pair.key] = pair.value });
	    }
	
	    for (var name in headers)
	      this.transport.setRequestHeader(name, headers[name]);
	  },
	
	  success: function() {
	    var status = this.getStatus();
	    return !status || (status >= 200 && status < 300);
	  },
	
	  getStatus: function() {
	    try {
	      return this.transport.status || 0;
	    } catch (e) { return 0 }
	  },
	
	  respondToReadyState: function(readyState) {
	    var state = Ajax.Request.Events[readyState], response = new Ajax.Response(this);
	
	    if (state == 'Complete') {
	      try {
	        this._complete = true;
	        (this.options['on' + response.status]
	         || this.options['on' + (this.success() ? 'Success' : 'Failure')]
	         || Prototype.emptyFunction)(response, response.headerJSON);
	      } catch (e) {
	        this.dispatchException(e);
	      }
	
	      var contentType = response.getHeader('Content-type');
	      if (this.options.evalJS == 'force'
	          || (this.options.evalJS && contentType
	          && contentType.match(/^\s*(text|application)\/(x-)?(java|ecma)script(;.*)?\s*$/i)))
	        this.evalResponse();
	    }
	
	    try {
	      (this.options['on' + state] || Prototype.emptyFunction)(response, response.headerJSON);
	      Ajax.Responders.dispatch('on' + state, this, response, response.headerJSON);
	    } catch (e) {
	      this.dispatchException(e);
	    }
	
	    if (state == 'Complete') {
	      // avoid memory leak in MSIE: clean up
	      this.transport.onreadystatechange = Prototype.emptyFunction;
	    }
	  },
	
	  getHeader: function(name) {
	    try {
	      return this.transport.getResponseHeader(name);
	    } catch (e) { return null }
	  },
	
	  evalResponse: function() {
	    try {
	      return eval((this.transport.responseText || '').unfilterJSON());
	    } catch (e) {
	      this.dispatchException(e);
	    }
	  },
	
	  dispatchException: function(exception) {
	    (this.options.onException || Prototype.emptyFunction)(this, exception);
	    Ajax.Responders.dispatch('onException', this, exception);
	  }
	});
	
	Ajax.Request.Events =
	  ['Uninitialized', 'Loading', 'Loaded', 'Interactive', 'Complete'];
	
	Ajax.Response = Class.create({
	  initialize: function(request){
	    this.request = request;
	    var transport  = this.transport  = request.transport,
	        readyState = this.readyState = transport.readyState;
	
	    if((readyState > 2 && !Prototype.Browser.IE) || readyState == 4) {
	      this.status       = this.getStatus();
	      this.statusText   = this.getStatusText();
	      this.responseText = String.interpret(transport.responseText);
	      this.headerJSON   = this._getHeaderJSON();
	    }
	
	    if(readyState == 4) {
	      var xml = transport.responseXML;
	      this.responseXML  = xml === undefined ? null : xml;
	      this.responseJSON = this._getResponseJSON();
	    }
	  },
	
	  status:      0,
	  statusText: '',
	
	  getStatus: Ajax.Request.prototype.getStatus,
	
	  getStatusText: function() {
	    try {
	      return this.transport.statusText || '';
	    } catch (e) { return '' }
	  },
	
	  getHeader: Ajax.Request.prototype.getHeader,
	
	  getAllHeaders: function() {
	    try {
	      return this.getAllResponseHeaders();
	    } catch (e) { return null }
	  },
	
	  getResponseHeader: function(name) {
	    return this.transport.getResponseHeader(name);
	  },
	
	  getAllResponseHeaders: function() {
	    return this.transport.getAllResponseHeaders();
	  },
	
	  _getHeaderJSON: function() {
	    var json = this.getHeader('X-JSON');
	    if (!json) return null;
	    json = decodeURIComponent(escape(json));
	    try {
	      return json.evalJSON(this.request.options.sanitizeJSON);
	    } catch (e) {
	      this.request.dispatchException(e);
	    }
	  },
	
	  _getResponseJSON: function() {
	    var options = this.request.options;
	    if (!options.evalJSON || (options.evalJSON != 'force' &&
	      !(this.getHeader('Content-type') || '').include('application/json')))
	        return null;
	    try {
	      return this.transport.responseText.evalJSON(options.sanitizeJSON);
	    } catch (e) {
	      this.request.dispatchException(e);
	    }
	  }
	});
	
	Ajax.Updater = Class.create(Ajax.Request, {
	  initialize: function($super, container, url, options) {
	    this.container = {
	      success: (container.success || container),
	      failure: (container.failure || (container.success ? null : container))
	    };
	
	    options = options || { };
	    var onComplete = options.onComplete;
	    options.onComplete = (function(response, param) {
	      this.updateContent(response.responseText);
	      if (Object.isFunction(onComplete)) onComplete(response, param);
	    }).bind(this);
	
	    $super(url, options);
	  },
	
	  updateContent: function(responseText) {
	    var receiver = this.container[this.success() ? 'success' : 'failure'],
	        options = this.options;
	
	    if (!options.evalScripts) responseText = responseText.stripScripts();
	
	    if (receiver = $(receiver)) {
	      if (options.insertion) {
	        if (Object.isString(options.insertion)) {
	          var insertion = { }; insertion[options.insertion] = responseText;
	          receiver.insert(insertion);
	        }
	        else options.insertion(receiver, responseText);
	      }
	      else receiver.update(responseText);
	    }
	
	    if (this.success()) {
	      if (this.onComplete) this.onComplete.bind(this).defer();
	    }
	  }
	});
	
	Ajax.PeriodicalUpdater = Class.create(Ajax.Base, {
	  initialize: function($super, container, url, options) {
	    $super(options);
	    this.onComplete = this.options.onComplete;
	
	    this.frequency = (this.options.frequency || 2);
	    this.decay = (this.options.decay || 1);
	
	    this.updater = { };
	    this.container = container;
	    this.url = url;
	
	    this.start();
	  },
	
	  start: function() {
	    this.options.onComplete = this.updateComplete.bind(this);
	    this.onTimerEvent();
	  },
	
	  stop: function() {
	    this.updater.options.onComplete = undefined;
	    clearTimeout(this.timer);
	    (this.onComplete || Prototype.emptyFunction).apply(this, arguments);
	  },
	
	  updateComplete: function(response) {
	    if (this.options.decay) {
	      this.decay = (response.responseText == this.lastText ?
	        this.decay * this.options.decay : 1);
	
	      this.lastText = response.responseText;
	    }
	    this.timer = this.onTimerEvent.bind(this).delay(this.decay * this.frequency);
	  },
	
	  onTimerEvent: function() {
	    this.updater = new Ajax.Updater(this.container, this.url, this.options);
	  }
	});
	function $(element) {
	  if (arguments.length > 1) {
	    for (var i = 0, elements = [], length = arguments.length; i < length; i++)
	      elements.push($(arguments[i]));
	    return elements;
	  }
	  if (Object.isString(element))
	    element = document.getElementById(element);
	  return Element.extend(element);
	}
	
	if (Prototype.BrowserFeatures.XPath) {
	  document._getElementsByXPath = function(expression, parentElement) {
	    var results = [];
	    var query = document.evaluate(expression, $(parentElement) || document,
	      null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
	    for (var i = 0, length = query.snapshotLength; i < length; i++)
	      results.push(Element.extend(query.snapshotItem(i)));
	    return results;
	  };
	}
	
	/*--------------------------------------------------------------------------*/
	
	if (!window.Node) var Node = { };
	
	if (!Node.ELEMENT_NODE) {
	  // DOM level 2 ECMAScript Language Binding
	  Object.extend(Node, {
	    ELEMENT_NODE: 1,
	    ATTRIBUTE_NODE: 2,
	    TEXT_NODE: 3,
	    CDATA_SECTION_NODE: 4,
	    ENTITY_REFERENCE_NODE: 5,
	    ENTITY_NODE: 6,
	    PROCESSING_INSTRUCTION_NODE: 7,
	    COMMENT_NODE: 8,
	    DOCUMENT_NODE: 9,
	    DOCUMENT_TYPE_NODE: 10,
	    DOCUMENT_FRAGMENT_NODE: 11,
	    NOTATION_NODE: 12
	  });
	}
	
	(function() {
	  var element = this.Element;
	  this.Element = function(tagName, attributes) {
	    attributes = attributes || { };
	    tagName = tagName.toLowerCase();
	    var cache = Element.cache;
	    if (Prototype.Browser.IE && attributes.name) {
	      tagName = '<' + tagName + ' name="' + attributes.name + '">';
	      delete attributes.name;
	      return Element.writeAttribute(document.createElement(tagName), attributes);
	    }
	    if (!cache[tagName]) cache[tagName] = Element.extend(document.createElement(tagName));
	    return Element.writeAttribute(cache[tagName].cloneNode(false), attributes);
	  };
	  Object.extend(this.Element, element || { });
	}).call(window);
	
	Element.cache = { };
	
	Element.Methods = {
	  visible: function(element) {
	    return $(element).style.display != 'none';
	  },
	
	  toggle: function(element) {
	    element = $(element);
	    Element[Element.visible(element) ? 'hide' : 'show'](element);
	    return element;
	  },
	
	  hide: function(element) {
	    $(element).style.display = 'none';
	    return element;
	  },
	
	  show: function(element) {
	    $(element).style.display = '';
	    return element;
	  },
	
	  remove: function(element) {
	    element = $(element);
	    element.parentNode.removeChild(element);
	    return element;
	  },
	
	  update: function(element, content) {
	    element = $(element);
	    if (content && content.toElement) content = content.toElement();
	    if (Object.isElement(content)) return element.update().insert(content);
	    content = Object.toHTML(content);
	    element.innerHTML = content.stripScripts();
	    content.evalScripts.bind(content).defer();
	    return element;
	  },
	
	  replace: function(element, content) {
	    element = $(element);
	    if (content && content.toElement) content = content.toElement();
	    else if (!Object.isElement(content)) {
	      content = Object.toHTML(content);
	      var range = element.ownerDocument.createRange();
	      range.selectNode(element);
	      content.evalScripts.bind(content).defer();
	      content = range.createContextualFragment(content.stripScripts());
	    }
	    element.parentNode.replaceChild(content, element);
	    return element;
	  },
	
	  insert: function(element, insertions) {
	    element = $(element);
	
	    if (Object.isString(insertions) || Object.isNumber(insertions) ||
	        Object.isElement(insertions) || (insertions && (insertions.toElement || insertions.toHTML)))
	          insertions = {bottom:insertions};
	
	    var content, t, range;
	
	    for (position in insertions) {
	      content  = insertions[position];
	      position = position.toLowerCase();
	      t = Element._insertionTranslations[position];
	
	      if (content && content.toElement) content = content.toElement();
	      if (Object.isElement(content)) {
	        t.insert(element, content);
	        continue;
	      }
	
	      content = Object.toHTML(content);
	
	      range = element.ownerDocument.createRange();
	      t.initializeRange(element, range);
	      t.insert(element, range.createContextualFragment(content.stripScripts()));
	
	      content.evalScripts.bind(content).defer();
	    }
	
	    return element;
	  },
	
	  wrap: function(element, wrapper, attributes) {
	    element = $(element);
	    if (Object.isElement(wrapper))
	      $(wrapper).writeAttribute(attributes || { });
	    else if (Object.isString(wrapper)) wrapper = new Element(wrapper, attributes);
	    else wrapper = new Element('div', wrapper);
	    if (element.parentNode)
	      element.parentNode.replaceChild(wrapper, element);
	    wrapper.appendChild(element);
	    return wrapper;
	  },
	
	  inspect: function(element) {
	    element = $(element);
	    var result = '<' + element.tagName.toLowerCase();
	    $H({'id': 'id', 'className': 'class'}).each(function(pair) {
	      var property = pair.first(), attribute = pair.last();
	      var value = (element[property] || '').toString();
	      if (value) result += ' ' + attribute + '=' + value.inspect(true);
	    });
	    return result + '>';
	  },
	
	  recursivelyCollect: function(element, property) {
	    element = $(element);
	    var elements = [];
	    while (element = element[property])
	      if (element.nodeType == 1)
	        elements.push(Element.extend(element));
	    return elements;
	  },
	
	  ancestors: function(element) {
	    return $(element).recursivelyCollect('parentNode');
	  },
	
	  descendants: function(element) {
	    return $A($(element).getElementsByTagName('*')).each(Element.extend);
	  },
	
	  firstDescendant: function(element) {
	    element = $(element).firstChild;
	    while (element && element.nodeType != 1) element = element.nextSibling;
	    return $(element);
	  },
	
	  immediateDescendants: function(element) {
	    if (!(element = $(element).firstChild)) return [];
	    while (element && element.nodeType != 1) element = element.nextSibling;
	    if (element) return [element].concat($(element).nextSiblings());
	    return [];
	  },
	
	  previousSiblings: function(element) {
	    return $(element).recursivelyCollect('previousSibling');
	  },
	
	  nextSiblings: function(element) {
	    return $(element).recursivelyCollect('nextSibling');
	  },
	
	  siblings: function(element) {
	    element = $(element);
	    return element.previousSiblings().reverse().concat(element.nextSiblings());
	  },
	
	  match: function(element, selector) {
	    if (Object.isString(selector))
	      selector = new Selector(selector);
	    return selector.match($(element));
	  },
	
	  up: function(element, expression, index) {
	    element = $(element);
	    if (arguments.length == 1) return $(element.parentNode);
	    var ancestors = element.ancestors();
	    return expression ? Selector.findElement(ancestors, expression, index) :
	      ancestors[index || 0];
	  },
	
	  down: function(element, expression, index) {
	    element = $(element);
	    if (arguments.length == 1) return element.firstDescendant();
	    var descendants = element.descendants();
	    return expression ? Selector.findElement(descendants, expression, index) :
	      descendants[index || 0];
	  },
	
	  previous: function(element, expression, index) {
	    element = $(element);
	    if (arguments.length == 1) return $(Selector.handlers.previousElementSibling(element));
	    var previousSiblings = element.previousSiblings();
	    return expression ? Selector.findElement(previousSiblings, expression, index) :
	      previousSiblings[index || 0];
	  },
	
	  next: function(element, expression, index) {
	    element = $(element);
	    if (arguments.length == 1) return $(Selector.handlers.nextElementSibling(element));
	    var nextSiblings = element.nextSiblings();
	    return expression ? Selector.findElement(nextSiblings, expression, index) :
	      nextSiblings[index || 0];
	  },
	
	  select: function() {
	    var args = $A(arguments), element = $(args.shift());
	    return Selector.findChildElements(element, args);
	  },
	
	  adjacent: function() {
	    var args = $A(arguments), element = $(args.shift());
	    return Selector.findChildElements(element.parentNode, args).without(element);
	  },
	
	  identify: function(element) {
	    element = $(element);
	    var id = element.readAttribute('id'), self = arguments.callee;
	    if (id) return id;
	    do { id = 'anonymous_element_' + self.counter++ } while ($(id));
	    element.writeAttribute('id', id);
	    return id;
	  },
	
	  readAttribute: function(element, name) {
	    element = $(element);
	    if (Prototype.Browser.IE) {
	      var t = Element._attributeTranslations.read;
	      if (t.values[name]) return t.values[name](element, name);
	      if (t.names[name]) name = t.names[name];
	      if (name.include(':')) {
	        return (!element.attributes || !element.attributes[name]) ? null :
	         element.attributes[name].value;
	      }
	    }
	    return element.getAttribute(name);
	  },
	
	  writeAttribute: function(element, name, value) {
	    element = $(element);
	    var attributes = { }, t = Element._attributeTranslations.write;
	
	    if (typeof name == 'object') attributes = name;
	    else attributes[name] = value === undefined ? true : value;
	
	    for (var attr in attributes) {
	      var name = t.names[attr] || attr, value = attributes[attr];
	      if (t.values[attr]) name = t.values[attr](element, value);
	      if (value === false || value === null)
	        element.removeAttribute(name);
	      else if (value === true)
	        element.setAttribute(name, name);
	      else element.setAttribute(name, value);
	    }
	    return element;
	  },
	
	  getHeight: function(element) {
	    return $(element).getDimensions().height;
	  },
	
	  getWidth: function(element) {
	    return $(element).getDimensions().width;
	  },
	
	  classNames: function(element) {
	    return new Element.ClassNames(element);
	  },
	
	  hasClassName: function(element, className) {
	    if (!(element = $(element))) return;
	    var elementClassName = element.className;
	    return (elementClassName.length > 0 && (elementClassName == className ||
	      new RegExp("(^|\\s)" + className + "(\\s|$)").test(elementClassName)));
	  },
	
	  addClassName: function(element, className) {
	    if (!(element = $(element))) return;
	    if (!element.hasClassName(className))
	      element.className += (element.className ? ' ' : '') + className;
	    return element;
	  },
	
	  removeClassName: function(element, className) {
	    if (!(element = $(element))) return;
	    element.className = element.className.replace(
	      new RegExp("(^|\\s+)" + className + "(\\s+|$)"), ' ').strip();
	    return element;
	  },
	
	  toggleClassName: function(element, className) {
	    if (!(element = $(element))) return;
	    return element[element.hasClassName(className) ?
	      'removeClassName' : 'addClassName'](className);
	  },
	
	  // removes whitespace-only text node children
	  cleanWhitespace: function(element) {
	    element = $(element);
	    var node = element.firstChild;
	    while (node) {
	      var nextNode = node.nextSibling;
	      if (node.nodeType == 3 && !/\S/.test(node.nodeValue))
	        element.removeChild(node);
	      node = nextNode;
	    }
	    return element;
	  },
	
	  empty: function(element) {
	    return $(element).innerHTML.blank();
	  },
	
	  descendantOf: function(element, ancestor) {
	    element = $(element), ancestor = $(ancestor);
	
	    if (element.compareDocumentPosition)
	      return (element.compareDocumentPosition(ancestor) & 8) === 8;
	
	    if (element.sourceIndex && !Prototype.Browser.Opera) {
	      var e = element.sourceIndex, a = ancestor.sourceIndex,
	       nextAncestor = ancestor.nextSibling;
	      if (!nextAncestor) {
	        do { ancestor = ancestor.parentNode; }
	        while (!(nextAncestor = ancestor.nextSibling) && ancestor.parentNode);
	      }
	      if (nextAncestor) return (e > a && e < nextAncestor.sourceIndex);
	    }
	
	    while (element = element.parentNode)
	      if (element == ancestor) return true;
	    return false;
	  },
	
	  scrollTo: function(element) {
	    element = $(element);
	    var pos = element.cumulativeOffset();
	    window.scrollTo(pos[0], pos[1]);
	    return element;
	  },
	
	  getStyle: function(element, style) {
	    element = $(element);
	    style = style == 'float' ? 'cssFloat' : style.camelize();
	    var value = element.style[style];
	    if (!value) {
	      var css = document.defaultView.getComputedStyle(element, null);
	      value = css ? css[style] : null;
	    }
	    if (style == 'opacity') return value ? parseFloat(value) : 1.0;
	    return value == 'auto' ? null : value;
	  },
	
	  getOpacity: function(element) {
	    return $(element).getStyle('opacity');
	  },
	
	  setStyle: function(element, styles) {
	    element = $(element);
	    var elementStyle = element.style, match;
	    if (Object.isString(styles)) {
	      element.style.cssText += ';' + styles;
	      return styles.include('opacity') ?
	        element.setOpacity(styles.match(/opacity:\s*(\d?\.?\d*)/)[1]) : element;
	    }
	    for (var property in styles)
	      if (property == 'opacity') element.setOpacity(styles[property]);
	      else
	        elementStyle[(property == 'float' || property == 'cssFloat') ?
	          (elementStyle.styleFloat === undefined ? 'cssFloat' : 'styleFloat') :
	            property] = styles[property];
	
	    return element;
	  },
	
	  setOpacity: function(element, value) {
	    element = $(element);
	    element.style.opacity = (value == 1 || value === '') ? '' :
	      (value < 0.00001) ? 0 : value;
	    return element;
	  },
	
	  getDimensions: function(element) {
	    element = $(element);
	    var display = $(element).getStyle('display');
	    if (display != 'none' && display != null) // Safari bug
	      return {width: element.offsetWidth, height: element.offsetHeight};
	
	    // All *Width and *Height properties give 0 on elements with display none,
	    // so enable the element temporarily
	    var els = element.style;
	    var originalVisibility = els.visibility;
	    var originalPosition = els.position;
	    var originalDisplay = els.display;
	    els.visibility = 'hidden';
	    els.position = 'absolute';
	    els.display = 'block';
	    var originalWidth = element.clientWidth;
	    var originalHeight = element.clientHeight;
	    els.display = originalDisplay;
	    els.position = originalPosition;
	    els.visibility = originalVisibility;
	    return {width: originalWidth, height: originalHeight};
	  },
	
	  makePositioned: function(element) {
	    element = $(element);
	    var pos = Element.getStyle(element, 'position');
	    if (pos == 'static' || !pos) {
	      element._madePositioned = true;
	      element.style.position = 'relative';
	      // Opera returns the offset relative to the positioning context, when an
	      // element is position relative but top and left have not been defined
	      if (window.opera) {
	        element.style.top = 0;
	        element.style.left = 0;
	      }
	    }
	    return element;
	  },
	
	  undoPositioned: function(element) {
	    element = $(element);
	    if (element._madePositioned) {
	      element._madePositioned = undefined;
	      element.style.position =
	        element.style.top =
	        element.style.left =
	        element.style.bottom =
	        element.style.right = '';
	    }
	    return element;
	  },
	
	  makeClipping: function(element) {
	    element = $(element);
	    if (element._overflow) return element;
	    element._overflow = Element.getStyle(element, 'overflow') || 'auto';
	    if (element._overflow !== 'hidden')
	      element.style.overflow = 'hidden';
	    return element;
	  },
	
	  undoClipping: function(element) {
	    element = $(element);
	    if (!element._overflow) return element;
	    element.style.overflow = element._overflow == 'auto' ? '' : element._overflow;
	    element._overflow = null;
	    return element;
	  },
	
	  cumulativeOffset: function(element) {
	    var valueT = 0, valueL = 0;
	    do {
	      valueT += element.offsetTop  || 0;
	      valueL += element.offsetLeft || 0;
	      element = element.offsetParent;
	    } while (element);
	    return Element._returnOffset(valueL, valueT);
	  },
	
	  positionedOffset: function(element) {
	    var valueT = 0, valueL = 0;
	    do {
	      valueT += element.offsetTop  || 0;
	      valueL += element.offsetLeft || 0;
	      element = element.offsetParent;
	      if (element) {
	        if (element.tagName == 'BODY') break;
	        var p = Element.getStyle(element, 'position');
	        if (p == 'relative' || p == 'absolute') break;
	      }
	    } while (element);
	    return Element._returnOffset(valueL, valueT);
	  },
	
	  absolutize: function(element) {
	    element = $(element);
	    if (element.getStyle('position') == 'absolute') return;
	    // Position.prepare(); // To be done manually by Scripty when it needs it.
	
	    var offsets = element.positionedOffset();
	    var top     = offsets[1];
	    var left    = offsets[0];
	    var width   = element.clientWidth;
	    var height  = element.clientHeight;
	
	    element._originalLeft   = left - parseFloat(element.style.left  || 0);
	    element._originalTop    = top  - parseFloat(element.style.top || 0);
	    element._originalWidth  = element.style.width;
	    element._originalHeight = element.style.height;
	
	    element.style.position = 'absolute';
	    element.style.top    = top + 'px';
	    element.style.left   = left + 'px';
	    element.style.width  = width + 'px';
	    element.style.height = height + 'px';
	    return element;
	  },
	
	  relativize: function(element) {
	    element = $(element);
	    if (element.getStyle('position') == 'relative') return;
	    // Position.prepare(); // To be done manually by Scripty when it needs it.
	
	    element.style.position = 'relative';
	    var top  = parseFloat(element.style.top  || 0) - (element._originalTop || 0);
	    var left = parseFloat(element.style.left || 0) - (element._originalLeft || 0);
	
	    element.style.top    = top + 'px';
	    element.style.left   = left + 'px';
	    element.style.height = element._originalHeight;
	    element.style.width  = element._originalWidth;
	    return element;
	  },
	
	  cumulativeScrollOffset: function(element) {
	    var valueT = 0, valueL = 0;
	    do {
	      valueT += element.scrollTop  || 0;
	      valueL += element.scrollLeft || 0;
	      element = element.parentNode;
	    } while (element);
	    return Element._returnOffset(valueL, valueT);
	  },
	
	  getOffsetParent: function(element) {
	    if (element.offsetParent) return $(element.offsetParent);
	    if (element == document.body) return $(element);
	
	    while ((element = element.parentNode) && element != document.body)
	      if (Element.getStyle(element, 'position') != 'static')
	        return $(element);
	
	    return $(document.body);
	  },
	
	  viewportOffset: function(forElement) {
	    var valueT = 0, valueL = 0;
	
	    var element = forElement;
	    do {
	      valueT += element.offsetTop  || 0;
	      valueL += element.offsetLeft || 0;
	
	      // Safari fix
	      if (element.offsetParent == document.body &&
	        Element.getStyle(element, 'position') == 'absolute') break;
	
	    } while (element = element.offsetParent);
	
	    element = forElement;
	    do {
	      if (!Prototype.Browser.Opera || element.tagName == 'BODY') {
	        valueT -= element.scrollTop  || 0;
	        valueL -= element.scrollLeft || 0;
	      }
	    } while (element = element.parentNode);
	
	    return Element._returnOffset(valueL, valueT);
	  },
	
	  clonePosition: function(element, source) {
	    var options = Object.extend({
	      setLeft:    true,
	      setTop:     true,
	      setWidth:   true,
	      setHeight:  true,
	      offsetTop:  0,
	      offsetLeft: 0
	    }, arguments[2] || { });
	
	    // find page position of source
	    source = $(source);
	    var p = source.viewportOffset();
	
	    // find coordinate system to use
	    element = $(element);
	    var delta = [0, 0];
	    var parent = null;
	    // delta [0,0] will do fine with position: fixed elements,
	    // position:absolute needs offsetParent deltas
	    if (Element.getStyle(element, 'position') == 'absolute') {
	      parent = element.getOffsetParent();
	      delta = parent.viewportOffset();
	    }
	
	    // correct by body offsets (fixes Safari)
	    if (parent == document.body) {
	      delta[0] -= document.body.offsetLeft;
	      delta[1] -= document.body.offsetTop;
	    }
	
	    // set position
	    if (options.setLeft)   element.style.left  = (p[0] - delta[0] + options.offsetLeft) + 'px';
	    if (options.setTop)    element.style.top   = (p[1] - delta[1] + options.offsetTop) + 'px';
	    if (options.setWidth)  element.style.width = source.offsetWidth + 'px';
	    if (options.setHeight) element.style.height = source.offsetHeight + 'px';
	    return element;
	  }
	};
	
	Element.Methods.identify.counter = 1;
	
	Object.extend(Element.Methods, {
	  getElementsBySelector: Element.Methods.select,
	  childElements: Element.Methods.immediateDescendants
	});
	
	Element._attributeTranslations = {
	  write: {
	    names: {
	      className: 'class',
	      htmlFor:   'for'
	    },
	    values: { }
	  }
	};
	
	
	if (!document.createRange || Prototype.Browser.Opera) {
	  Element.Methods.insert = function(element, insertions) {
	    element = $(element);
	
	    if (Object.isString(insertions) || Object.isNumber(insertions) ||
	        Object.isElement(insertions) || (insertions && (insertions.toElement || insertions.toHTML)))
	          insertions = { bottom: insertions };
	
	    var t = Element._insertionTranslations, content, position, pos, tagName;
	
	    for (position in insertions) {
	      content  = insertions[position];
	      position = position.toLowerCase();
	      pos      = t[position];
	
	      if (content && content.toElement) content = content.toElement();
	      if (Object.isElement(content)) {
	        pos.insert(element, content);
	        continue;
	      }
	
	      content = Object.toHTML(content);
	      tagName = ((position == 'before' || position == 'after')
	        ? element.parentNode : element).tagName.toUpperCase();
	
	      if (t.tags[tagName]) {
	        var fragments = Element._getContentFromAnonymousElement(tagName, content.stripScripts());
	        if (position == 'top' || position == 'after') fragments.reverse();
	        fragments.each(pos.insert.curry(element));
	      }
	      else element.insertAdjacentHTML(pos.adjacency, content.stripScripts());
	
	      content.evalScripts.bind(content).defer();
	    }
	
	    return element;
	  };
	}
	
	if (Prototype.Browser.Opera) {
	  Element.Methods._getStyle = Element.Methods.getStyle;
	  Element.Methods.getStyle = function(element, style) {
	    switch(style) {
	      case 'left':
	      case 'top':
	      case 'right':
	      case 'bottom':
	        if (Element._getStyle(element, 'position') == 'static') return null;
	      default: return Element._getStyle(element, style);
	    }
	  };
	  Element.Methods._readAttribute = Element.Methods.readAttribute;
	  Element.Methods.readAttribute = function(element, attribute) {
	    if (attribute == 'title') return element.title;
	    return Element._readAttribute(element, attribute);
	  };
	}
	
	else if (Prototype.Browser.IE) {
	  $w('positionedOffset getOffsetParent viewportOffset').each(function(method) {
	    Element.Methods[method] = Element.Methods[method].wrap(
	      function(proceed, element) {
	        element = $(element);
	        var position = element.getStyle('position');
	        if (position != 'static') return proceed(element);
	        element.setStyle({ position: 'relative' });
	        var value = proceed(element);
	        element.setStyle({ position: position });
	        return value;
	      }
	    );
	  });
	
	  Element.Methods.getStyle = function(element, style) {
	    element = $(element);
	    style = (style == 'float' || style == 'cssFloat') ? 'styleFloat' : style.camelize();
	    var value = element.style[style];
	    if (!value && element.currentStyle) value = element.currentStyle[style];
	
	    if (style == 'opacity') {
	      if (value = (element.getStyle('filter') || '').match(/alpha\(opacity=(.*)\)/))
	        if (value[1]) return parseFloat(value[1]) / 100;
	      return 1.0;
	    }
	
	    if (value == 'auto') {
	      if ((style == 'width' || style == 'height') && (element.getStyle('display') != 'none'))
	        return element['offset' + style.capitalize()] + 'px';
	      return null;
	    }
	    return value;
	  };
	
	  Element.Methods.setOpacity = function(element, value) {
	    function stripAlpha(filter){
	      return filter.replace(/alpha\([^\)]*\)/gi,'');
	    }
	    element = $(element);
	    var currentStyle = element.currentStyle;
	    if ((currentStyle && !currentStyle.hasLayout) ||
	      (!currentStyle && element.style.zoom == 'normal'))
	        element.style.zoom = 1;
	
	    var filter = element.getStyle('filter'), style = element.style;
	    if (value == 1 || value === '') {
	      (filter = stripAlpha(filter)) ?
	        style.filter = filter : style.removeAttribute('filter');
	      return element;
	    } else if (value < 0.00001) value = 0;
	    style.filter = stripAlpha(filter) +
	      'alpha(opacity=' + (value * 100) + ')';
	    return element;
	  };
	
	  Element._attributeTranslations = {
	    read: {
	      names: {
	        'class': 'className',
	        'for':   'htmlFor'
	      },
	      values: {
	        _getAttr: function(element, attribute) {
	          return element.getAttribute(attribute, 2);
	        },
	        _getAttrNode: function(element, attribute) {
	          var node = element.getAttributeNode(attribute);
	          return node ? node.value : "";
	        },
	        _getEv: function(element, attribute) {
	          var attribute = element.getAttribute(attribute);
	          return attribute ? attribute.toString().slice(23, -2) : null;
	        },
	        _flag: function(element, attribute) {
	          return $(element).hasAttribute(attribute) ? attribute : null;
	        },
	        style: function(element) {
	          return element.style.cssText.toLowerCase();
	        },
	        title: function(element) {
	          return element.title;
	        }
	      }
	    }
	  };
	
	  Element._attributeTranslations.write = {
	    names: Object.clone(Element._attributeTranslations.read.names),
	    values: {
	      checked: function(element, value) {
	        element.checked = !!value;
	      },
	
	      style: function(element, value) {
	        element.style.cssText = value ? value : '';
	      }
	    }
	  };
	
	  Element._attributeTranslations.has = {};
	
	  $w('colSpan rowSpan vAlign dateTime accessKey tabIndex ' +
	      'encType maxLength readOnly longDesc').each(function(attr) {
	    Element._attributeTranslations.write.names[attr.toLowerCase()] = attr;
	    Element._attributeTranslations.has[attr.toLowerCase()] = attr;
	  });
	
	  (function(v) {
	    Object.extend(v, {
	      href:        v._getAttr,
	      src:         v._getAttr,
	      type:        v._getAttr,
	      action:      v._getAttrNode,
	      disabled:    v._flag,
	      checked:     v._flag,
	      readonly:    v._flag,
	      multiple:    v._flag,
	      onload:      v._getEv,
	      onunload:    v._getEv,
	      onclick:     v._getEv,
	      ondblclick:  v._getEv,
	      onmousedown: v._getEv,
	      onmouseup:   v._getEv,
	      onmouseover: v._getEv,
	      onmousemove: v._getEv,
	      onmouseout:  v._getEv,
	      onfocus:     v._getEv,
	      onblur:      v._getEv,
	      onkeypress:  v._getEv,
	      onkeydown:   v._getEv,
	      onkeyup:     v._getEv,
	      onsubmit:    v._getEv,
	      onreset:     v._getEv,
	      onselect:    v._getEv,
	      onchange:    v._getEv
	    });
	  })(Element._attributeTranslations.read.values);
	}
	
	else if (Prototype.Browser.Gecko && /rv:1\.8\.0/.test(navigator.userAgent)) {
	  Element.Methods.setOpacity = function(element, value) {
	    element = $(element);
	    element.style.opacity = (value == 1) ? 0.999999 :
	      (value === '') ? '' : (value < 0.00001) ? 0 : value;
	    return element;
	  };
	}
	
	else if (Prototype.Browser.WebKit) {
	  Element.Methods.setOpacity = function(element, value) {
	    element = $(element);
	    element.style.opacity = (value == 1 || value === '') ? '' :
	      (value < 0.00001) ? 0 : value;
	
	    if (value == 1)
	      if(element.tagName == 'IMG' && element.width) {
	        element.width++; element.width--;
	      } else try {
	        var n = document.createTextNode(' ');
	        element.appendChild(n);
	        element.removeChild(n);
	      } catch (e) { }
	
	    return element;
	  };
	
	  // Safari returns margins on body which is incorrect if the child is absolutely
	  // positioned.  For performance reasons, redefine Position.cumulativeOffset for
	  // KHTML/WebKit only.
	  Element.Methods.cumulativeOffset = function(element) {
	    var valueT = 0, valueL = 0;
	    do {
	      valueT += element.offsetTop  || 0;
	      valueL += element.offsetLeft || 0;
	      if (element.offsetParent == document.body)
	        if (Element.getStyle(element, 'position') == 'absolute') break;
	
	      element = element.offsetParent;
	    } while (element);
	
	    return Element._returnOffset(valueL, valueT);
	  };
	}
	
	if (Prototype.Browser.IE || Prototype.Browser.Opera) {
	  // IE and Opera are missing .innerHTML support for TABLE-related and SELECT elements
	  Element.Methods.update = function(element, content) {
	    element = $(element);
	
	    if (content && content.toElement) content = content.toElement();
	    if (Object.isElement(content)) return element.update().insert(content);
	
	    content = Object.toHTML(content);
	    var tagName = element.tagName.toUpperCase();
	
	    if (tagName in Element._insertionTranslations.tags) {
	      $A(element.childNodes).each(function(node) { element.removeChild(node) });
	      Element._getContentFromAnonymousElement(tagName, content.stripScripts())
	        .each(function(node) { element.appendChild(node) });
	    }
	    else element.innerHTML = content.stripScripts();
	
	    content.evalScripts.bind(content).defer();
	    return element;
	  };
	}
	
	if (document.createElement('div').outerHTML) {
	  Element.Methods.replace = function(element, content) {
	    element = $(element);
	
	    if (content && content.toElement) content = content.toElement();
	    if (Object.isElement(content)) {
	      element.parentNode.replaceChild(content, element);
	      return element;
	    }
	
	    content = Object.toHTML(content);
	    var parent = element.parentNode, tagName = parent.tagName.toUpperCase();
	
	    if (Element._insertionTranslations.tags[tagName]) {
	      var nextSibling = element.next();
	      var fragments = Element._getContentFromAnonymousElement(tagName, content.stripScripts());
	      parent.removeChild(element);
	      if (nextSibling)
	        fragments.each(function(node) { parent.insertBefore(node, nextSibling) });
	      else
	        fragments.each(function(node) { parent.appendChild(node) });
	    }
	    else element.outerHTML = content.stripScripts();
	
	    content.evalScripts.bind(content).defer();
	    return element;
	  };
	}
	
	Element._returnOffset = function(l, t) {
	  var result = [l, t];
	  result.left = l;
	  result.top = t;
	  return result;
	};
	
	Element._getContentFromAnonymousElement = function(tagName, html) {
	  var div = new Element('div'), t = Element._insertionTranslations.tags[tagName];
	  div.innerHTML = t[0] + html + t[1];
	  t[2].times(function() { div = div.firstChild });
	  return $A(div.childNodes);
	};
	
	Element._insertionTranslations = {
	  before: {
	    adjacency: 'beforeBegin',
	    insert: function(element, node) {
	      element.parentNode.insertBefore(node, element);
	    },
	    initializeRange: function(element, range) {
	      range.setStartBefore(element);
	    }
	  },
	  top: {
	    adjacency: 'afterBegin',
	    insert: function(element, node) {
	      element.insertBefore(node, element.firstChild);
	    },
	    initializeRange: function(element, range) {
	      range.selectNodeContents(element);
	      range.collapse(true);
	    }
	  },
	  bottom: {
	    adjacency: 'beforeEnd',
	    insert: function(element, node) {
	      element.appendChild(node);
	    }
	  },
	  after: {
	    adjacency: 'afterEnd',
	    insert: function(element, node) {
	      element.parentNode.insertBefore(node, element.nextSibling);
	    },
	    initializeRange: function(element, range) {
	      range.setStartAfter(element);
	    }
	  },
	  tags: {
	    TABLE:  ['<table>',                '</table>',                   1],
	    TBODY:  ['<table><tbody>',         '</tbody></table>',           2],
	    TR:     ['<table><tbody><tr>',     '</tr></tbody></table>',      3],
	    TD:     ['<table><tbody><tr><td>', '</td></tr></tbody></table>', 4],
	    SELECT: ['<select>',               '</select>',                  1]
	  }
	};
	
	(function() {
	  this.bottom.initializeRange = this.top.initializeRange;
	  Object.extend(this.tags, {
	    THEAD: this.tags.TBODY,
	    TFOOT: this.tags.TBODY,
	    TH:    this.tags.TD
	  });
	}).call(Element._insertionTranslations);
	
	Element.Methods.Simulated = {
	  hasAttribute: function(element, attribute) {
	    attribute = Element._attributeTranslations.has[attribute] || attribute;
	    var node = $(element).getAttributeNode(attribute);
	    return node && node.specified;
	  }
	};
	
	Element.Methods.ByTag = { };
	
	Object.extend(Element, Element.Methods);
	
	if (!Prototype.BrowserFeatures.ElementExtensions &&
	    document.createElement('div').__proto__) {
	  window.HTMLElement = { };
	  window.HTMLElement.prototype = document.createElement('div').__proto__;
	  Prototype.BrowserFeatures.ElementExtensions = true;
	}
	
	Element.extend = (function() {
	  if (Prototype.BrowserFeatures.SpecificElementExtensions)
	    return Prototype.K;
	
	  var Methods = { }, ByTag = Element.Methods.ByTag;
	
	  var extend = Object.extend(function(element) {
	    if (!element || element._extendedByPrototype ||
	        element.nodeType != 1 || element == window) return element;
	
	    var methods = Object.clone(Methods),
	      tagName = element.tagName, property, value;
	
	    // extend methods for specific tags
	    if (ByTag[tagName]) Object.extend(methods, ByTag[tagName]);
	
	    for (property in methods) {
	      value = methods[property];
	      if (Object.isFunction(value) && !(property in element))
	        element[property] = value.methodize();
	    }
	
	    element._extendedByPrototype = Prototype.emptyFunction;
	    return element;
	
	  }, {
	    refresh: function() {
	      // extend methods for all tags (Safari doesn't need this)
	      if (!Prototype.BrowserFeatures.ElementExtensions) {
	        Object.extend(Methods, Element.Methods);
	        Object.extend(Methods, Element.Methods.Simulated);
	      }
	    }
	  });
	
	  extend.refresh();
	  return extend;
	})();
	
	Element.hasAttribute = function(element, attribute) {
	  if (element.hasAttribute) return element.hasAttribute(attribute);
	  return Element.Methods.Simulated.hasAttribute(element, attribute);
	};
	
	Element.addMethods = function(methods) {
	  var F = Prototype.BrowserFeatures, T = Element.Methods.ByTag;
	
	  if (!methods) {
	    Object.extend(Form, Form.Methods);
	    Object.extend(Form.Element, Form.Element.Methods);
	    Object.extend(Element.Methods.ByTag, {
	      "FORM":     Object.clone(Form.Methods),
	      "INPUT":    Object.clone(Form.Element.Methods),
	      "SELECT":   Object.clone(Form.Element.Methods),
	      "TEXTAREA": Object.clone(Form.Element.Methods)
	    });
	  }
	
	  if (arguments.length == 2) {
	    var tagName = methods;
	    methods = arguments[1];
	  }
	
	  if (!tagName) Object.extend(Element.Methods, methods || { });
	  else {
	    if (Object.isArray(tagName)) tagName.each(extend);
	    else extend(tagName);
	  }
	
	  function extend(tagName) {
	    tagName = tagName.toUpperCase();
	    if (!Element.Methods.ByTag[tagName])
	      Element.Methods.ByTag[tagName] = { };
	    Object.extend(Element.Methods.ByTag[tagName], methods);
	  }
	
	  function copy(methods, destination, onlyIfAbsent) {
	    onlyIfAbsent = onlyIfAbsent || false;
	    for (var property in methods) {
	      var value = methods[property];
	      if (!Object.isFunction(value)) continue;
	      if (!onlyIfAbsent || !(property in destination))
	        destination[property] = value.methodize();
	    }
	  }
	
	  function findDOMClass(tagName) {
	    var klass;
	    var trans = {
	      "OPTGROUP": "OptGroup", "TEXTAREA": "TextArea", "P": "Paragraph",
	      "FIELDSET": "FieldSet", "UL": "UList", "OL": "OList", "DL": "DList",
	      "DIR": "Directory", "H1": "Heading", "H2": "Heading", "H3": "Heading",
	      "H4": "Heading", "H5": "Heading", "H6": "Heading", "Q": "Quote",
	      "INS": "Mod", "DEL": "Mod", "A": "Anchor", "IMG": "Image", "CAPTION":
	      "TableCaption", "COL": "TableCol", "COLGROUP": "TableCol", "THEAD":
	      "TableSection", "TFOOT": "TableSection", "TBODY": "TableSection", "TR":
	      "TableRow", "TH": "TableCell", "TD": "TableCell", "FRAMESET":
	      "FrameSet", "IFRAME": "IFrame"
	    };
	    if (trans[tagName]) klass = 'HTML' + trans[tagName] + 'Element';
	    if (window[klass]) return window[klass];
	    klass = 'HTML' + tagName + 'Element';
	    if (window[klass]) return window[klass];
	    klass = 'HTML' + tagName.capitalize() + 'Element';
	    if (window[klass]) return window[klass];
	
	    window[klass] = { };
	    window[klass].prototype = document.createElement(tagName).__proto__;
	    return window[klass];
	  }
	
	  if (F.ElementExtensions) {
	    copy(Element.Methods, HTMLElement.prototype);
	    copy(Element.Methods.Simulated, HTMLElement.prototype, true);
	  }
	
	  if (F.SpecificElementExtensions) {
	    for (var tag in Element.Methods.ByTag) {
	      var klass = findDOMClass(tag);
	      if (Object.isUndefined(klass)) continue;
	      copy(T[tag], klass.prototype);
	    }
	  }
	
	  Object.extend(Element, Element.Methods);
	  delete Element.ByTag;
	
	  if (Element.extend.refresh) Element.extend.refresh();
	  Element.cache = { };
	};
	
	document.viewport = {
	  getDimensions: function() {
	    var dimensions = { };
	    $w('width height').each(function(d) {
	      var D = d.capitalize();
	      dimensions[d] = self['inner' + D] ||
	       (document.documentElement['client' + D] || document.body['client' + D]);
	    });
	    return dimensions;
	  },
	
	  getWidth: function() {
	    return this.getDimensions().width;
	  },
	
	  getHeight: function() {
	    return this.getDimensions().height;
	  },
	
	  getScrollOffsets: function() {
	    return Element._returnOffset(
	      window.pageXOffset || document.documentElement.scrollLeft || document.body.scrollLeft,
	      window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop);
	  }
	};
	/* Portions of the Selector class are derived from Jack Slocum’s DomQuery,
	 * part of YUI-Ext version 0.40, distributed under the terms of an MIT-style
	 * license.  Please see http://www.yui-ext.com/ for more information. */
	
	var Selector = Class.create({
	  initialize: function(expression) {
	    this.expression = expression.strip();
	    this.compileMatcher();
	  },
	
	  compileMatcher: function() {
	    // Selectors with namespaced attributes can't use the XPath version
	    if (Prototype.BrowserFeatures.XPath && !(/(\[[\w-]*?:|:checked)/).test(this.expression))
	      return this.compileXPathMatcher();
	
	    var e = this.expression, ps = Selector.patterns, h = Selector.handlers,
	        c = Selector.criteria, le, p, m;
	
	    if (Selector._cache[e]) {
	      this.matcher = Selector._cache[e];
	      return;
	    }
	
	    this.matcher = ["this.matcher = function(root) {",
	                    "var r = root, h = Selector.handlers, c = false, n;"];
	
	    while (e && le != e && (/\S/).test(e)) {
	      le = e;
	      for (var i in ps) {
	        p = ps[i];
	        if (m = e.match(p)) {
	          this.matcher.push(Object.isFunction(c[i]) ? c[i](m) :
	    	      new Template(c[i]).evaluate(m));
	          e = e.replace(m[0], '');
	          break;
	        }
	      }
	    }
	
	    this.matcher.push("return h.unique(n);\n}");
	    eval(this.matcher.join('\n'));
	    Selector._cache[this.expression] = this.matcher;
	  },
	
	  compileXPathMatcher: function() {
	    var e = this.expression, ps = Selector.patterns,
	        x = Selector.xpath, le, m;
	
	    if (Selector._cache[e]) {
	      this.xpath = Selector._cache[e]; return;
	    }
	
	    this.matcher = ['.//*'];
	    while (e && le != e && (/\S/).test(e)) {
	      le = e;
	      for (var i in ps) {
	        if (m = e.match(ps[i])) {
	          this.matcher.push(Object.isFunction(x[i]) ? x[i](m) :
	            new Template(x[i]).evaluate(m));
	          e = e.replace(m[0], '');
	          break;
	        }
	      }
	    }
	
	    this.xpath = this.matcher.join('');
	    Selector._cache[this.expression] = this.xpath;
	  },
	
	  findElements: function(root) {
	    root = root || document;
	    if (this.xpath) return document._getElementsByXPath(this.xpath, root);
	    return this.matcher(root);
	  },
	
	  match: function(element) {
	    this.tokens = [];
	
	    var e = this.expression, ps = Selector.patterns, as = Selector.assertions;
	    var le, p, m;
	
	    while (e && le !== e && (/\S/).test(e)) {
	      le = e;
	      for (var i in ps) {
	        p = ps[i];
	        if (m = e.match(p)) {
	          // use the Selector.assertions methods unless the selector
	          // is too complex.
	          if (as[i]) {
	            this.tokens.push([i, Object.clone(m)]);
	            e = e.replace(m[0], '');
	          } else {
	            // reluctantly do a document-wide search
	            // and look for a match in the array
	            return this.findElements(document).include(element);
	          }
	        }
	      }
	    }
	
	    var match = true, name, matches;
	    for (var i = 0, token; token = this.tokens[i]; i++) {
	      name = token[0], matches = token[1];
	      if (!Selector.assertions[name](element, matches)) {
	        match = false; break;
	      }
	    }
	
	    return match;
	  },
	
	  toString: function() {
	    return this.expression;
	  },
	
	  inspect: function() {
	    return "#<Selector:" + this.expression.inspect() + ">";
	  }
	});
	
	Object.extend(Selector, {
	  _cache: { },
	
	  xpath: {
	    descendant:   "//*",
	    child:        "/*",
	    adjacent:     "/following-sibling::*[1]",
	    laterSibling: '/following-sibling::*',
	    tagName:      function(m) {
	      if (m[1] == '*') return '';
	      return "[local-name()='" + m[1].toLowerCase() +
	             "' or local-name()='" + m[1].toUpperCase() + "']";
	    },
	    className:    "[contains(concat(' ', @class, ' '), ' #{1} ')]",
	    id:           "[@id='#{1}']",
	    attrPresence: "[@#{1}]",
	    attr: function(m) {
	      m[3] = m[5] || m[6];
	      return new Template(Selector.xpath.operators[m[2]]).evaluate(m);
	    },
	    pseudo: function(m) {
	      var h = Selector.xpath.pseudos[m[1]];
	      if (!h) return '';
	      if (Object.isFunction(h)) return h(m);
	      return new Template(Selector.xpath.pseudos[m[1]]).evaluate(m);
	    },
	    operators: {
	      '=':  "[@#{1}='#{3}']",
	      '!=': "[@#{1}!='#{3}']",
	      '^=': "[starts-with(@#{1}, '#{3}')]",
	      '$=': "[substring(@#{1}, (string-length(@#{1}) - string-length('#{3}') + 1))='#{3}']",
	      '*=': "[contains(@#{1}, '#{3}')]",
	      '~=': "[contains(concat(' ', @#{1}, ' '), ' #{3} ')]",
	      '|=': "[contains(concat('-', @#{1}, '-'), '-#{3}-')]"
	    },
	    pseudos: {
	      'first-child': '[not(preceding-sibling::*)]',
	      'last-child':  '[not(following-sibling::*)]',
	      'only-child':  '[not(preceding-sibling::* or following-sibling::*)]',
	      'empty':       "[count(*) = 0 and (count(text()) = 0 or translate(text(), ' \t\r\n', '') = '')]",
	      'checked':     "[@checked]",
	      'disabled':    "[@disabled]",
	      'enabled':     "[not(@disabled)]",
	      'not': function(m) {
	        var e = m[6], p = Selector.patterns,
	            x = Selector.xpath, le, m, v;
	
	        var exclusion = [];
	        while (e && le != e && (/\S/).test(e)) {
	          le = e;
	          for (var i in p) {
	            if (m = e.match(p[i])) {
	              v = Object.isFunction(x[i]) ? x[i](m) : new Template(x[i]).evaluate(m);
	              exclusion.push("(" + v.substring(1, v.length - 1) + ")");
	              e = e.replace(m[0], '');
	              break;
	            }
	          }
	        }
	        return "[not(" + exclusion.join(" and ") + ")]";
	      },
	      'nth-child':      function(m) {
	        return Selector.xpath.pseudos.nth("(count(./preceding-sibling::*) + 1) ", m);
	      },
	      'nth-last-child': function(m) {
	        return Selector.xpath.pseudos.nth("(count(./following-sibling::*) + 1) ", m);
	      },
	      'nth-of-type':    function(m) {
	        return Selector.xpath.pseudos.nth("position() ", m);
	      },
	      'nth-last-of-type': function(m) {
	        return Selector.xpath.pseudos.nth("(last() + 1 - position()) ", m);
	      },
	      'first-of-type':  function(m) {
	        m[6] = "1"; return Selector.xpath.pseudos['nth-of-type'](m);
	      },
	      'last-of-type':   function(m) {
	        m[6] = "1"; return Selector.xpath.pseudos['nth-last-of-type'](m);
	      },
	      'only-of-type':   function(m) {
	        var p = Selector.xpath.pseudos; return p['first-of-type'](m) + p['last-of-type'](m);
	      },
	      nth: function(fragment, m) {
	        var mm, formula = m[6], predicate;
	        if (formula == 'even') formula = '2n+0';
	        if (formula == 'odd')  formula = '2n+1';
	        if (mm = formula.match(/^(\d+)$/)) // digit only
	          return '[' + fragment + "= " + mm[1] + ']';
	        if (mm = formula.match(/^(-?\d*)?n(([+-])(\d+))?/)) { // an+b
	          if (mm[1] == "-") mm[1] = -1;
	          var a = mm[1] ? Number(mm[1]) : 1;
	          var b = mm[2] ? Number(mm[2]) : 0;
	          predicate = "[((#{fragment} - #{b}) mod #{a} = 0) and " +
	          "((#{fragment} - #{b}) div #{a} >= 0)]";
	          return new Template(predicate).evaluate({
	            fragment: fragment, a: a, b: b });
	        }
	      }
	    }
	  },
	
	  criteria: {
	    tagName:      'n = h.tagName(n, r, "#{1}", c);   c = false;',
	    className:    'n = h.className(n, r, "#{1}", c); c = false;',
	    id:           'n = h.id(n, r, "#{1}", c);        c = false;',
	    attrPresence: 'n = h.attrPresence(n, r, "#{1}"); c = false;',
	    attr: function(m) {
	      m[3] = (m[5] || m[6]);
	      return new Template('n = h.attr(n, r, "#{1}", "#{3}", "#{2}"); c = false;').evaluate(m);
	    },
	    pseudo: function(m) {
	      if (m[6]) m[6] = m[6].replace(/"/g, '\\"');
	      return new Template('n = h.pseudo(n, "#{1}", "#{6}", r, c); c = false;').evaluate(m);
	    },
	    descendant:   'c = "descendant";',
	    child:        'c = "child";',
	    adjacent:     'c = "adjacent";',
	    laterSibling: 'c = "laterSibling";'
	  },
	
	  patterns: {
	    // combinators must be listed first
	    // (and descendant needs to be last combinator)
	    laterSibling: /^\s*~\s*/,
	    child:        /^\s*>\s*/,
	    adjacent:     /^\s*\+\s*/,
	    descendant:   /^\s/,
	
	    // selectors follow
	    tagName:      /^\s*(\*|[\w\-]+)(\b|$)?/,
	    id:           /^#([\w\-\*]+)(\b|$)/,
	    className:    /^\.([\w\-\*]+)(\b|$)/,
	    pseudo:       /^:((first|last|nth|nth-last|only)(-child|-of-type)|empty|checked|(en|dis)abled|not)(\((.*?)\))?(\b|$|(?=\s)|(?=:))/,
	    attrPresence: /^\[([\w]+)\]/,
	    attr:         /\[((?:[\w-]*:)?[\w-]+)\s*(?:([!^$*~|]?=)\s*((['"])([^\4]*?)\4|([^'"][^\]]*?)))?\]/
	  },
	
	  // for Selector.match and Element#match
	  assertions: {
	    tagName: function(element, matches) {
	      return matches[1].toUpperCase() == element.tagName.toUpperCase();
	    },
	
	    className: function(element, matches) {
	      return Element.hasClassName(element, matches[1]);
	    },
	
	    id: function(element, matches) {
	      return element.id === matches[1];
	    },
	
	    attrPresence: function(element, matches) {
	      return Element.hasAttribute(element, matches[1]);
	    },
	
	    attr: function(element, matches) {
	      var nodeValue = Element.readAttribute(element, matches[1]);
	      return Selector.operators[matches[2]](nodeValue, matches[3]);
	    }
	  },
	
	  handlers: {
	    // UTILITY FUNCTIONS
	    // joins two collections
	    concat: function(a, b) {
	      for (var i = 0, node; node = b[i]; i++)
	        a.push(node);
	      return a;
	    },
	
	    // marks an array of nodes for counting
	    mark: function(nodes) {
	      for (var i = 0, node; node = nodes[i]; i++)
	        node._counted = true;
	      return nodes;
	    },
	
	    unmark: function(nodes) {
	      for (var i = 0, node; node = nodes[i]; i++)
	        node._counted = undefined;
	      return nodes;
	    },
	
	    // mark each child node with its position (for nth calls)
	    // "ofType" flag indicates whether we're indexing for nth-of-type
	    // rather than nth-child
	    index: function(parentNode, reverse, ofType) {
	      parentNode._counted = true;
	      if (reverse) {
	        for (var nodes = parentNode.childNodes, i = nodes.length - 1, j = 1; i >= 0; i--) {
	          var node = nodes[i];
	          if (node.nodeType == 1 && (!ofType || node._counted)) node.nodeIndex = j++;
	        }
	      } else {
	        for (var i = 0, j = 1, nodes = parentNode.childNodes; node = nodes[i]; i++)
	          if (node.nodeType == 1 && (!ofType || node._counted)) node.nodeIndex = j++;
	      }
	    },
	
	    // filters out duplicates and extends all nodes
	    unique: function(nodes) {
	      if (nodes.length == 0) return nodes;
	      var results = [], n;
	      for (var i = 0, l = nodes.length; i < l; i++)
	        if (!(n = nodes[i])._counted) {
	          n._counted = true;
	          results.push(Element.extend(n));
	        }
	      return Selector.handlers.unmark(results);
	    },
	
	    // COMBINATOR FUNCTIONS
	    descendant: function(nodes) {
	      var h = Selector.handlers;
	      for (var i = 0, results = [], node; node = nodes[i]; i++)
	        h.concat(results, node.getElementsByTagName('*'));
	      return results;
	    },
	
	    child: function(nodes) {
	      var h = Selector.handlers;
	      for (var i = 0, results = [], node; node = nodes[i]; i++) {
	        for (var j = 0, children = [], child; child = node.childNodes[j]; j++)
	          if (child.nodeType == 1 && child.tagName != '!') results.push(child);
	      }
	      return results;
	    },
	
	    adjacent: function(nodes) {
	      for (var i = 0, results = [], node; node = nodes[i]; i++) {
	        var next = this.nextElementSibling(node);
	        if (next) results.push(next);
	      }
	      return results;
	    },
	
	    laterSibling: function(nodes) {
	      var h = Selector.handlers;
	      for (var i = 0, results = [], node; node = nodes[i]; i++)
	        h.concat(results, Element.nextSiblings(node));
	      return results;
	    },
	
	    nextElementSibling: function(node) {
	      while (node = node.nextSibling)
		      if (node.nodeType == 1) return node;
	      return null;
	    },
	
	    previousElementSibling: function(node) {
	      while (node = node.previousSibling)
	        if (node.nodeType == 1) return node;
	      return null;
	    },
	
	    // TOKEN FUNCTIONS
	    tagName: function(nodes, root, tagName, combinator) {
	      tagName = tagName.toUpperCase();
	      var results = [], h = Selector.handlers;
	      if (nodes) {
	        if (combinator) {
	          // fastlane for ordinary descendant combinators
	          if (combinator == "descendant") {
	            for (var i = 0, node; node = nodes[i]; i++)
	              h.concat(results, node.getElementsByTagName(tagName));
	            return results;
	          } else nodes = this[combinator](nodes);
	          if (tagName == "*") return nodes;
	        }
	        for (var i = 0, node; node = nodes[i]; i++)
	          if (node.tagName.toUpperCase() == tagName) results.push(node);
	        return results;
	      } else return root.getElementsByTagName(tagName);
	    },
	
	    id: function(nodes, root, id, combinator) {
	      var targetNode = $(id), h = Selector.handlers;
	      if (!targetNode) return [];
	      if (!nodes && root == document) return [targetNode];
	      if (nodes) {
	        if (combinator) {
	          if (combinator == 'child') {
	            for (var i = 0, node; node = nodes[i]; i++)
	              if (targetNode.parentNode == node) return [targetNode];
	          } else if (combinator == 'descendant') {
	            for (var i = 0, node; node = nodes[i]; i++)
	              if (Element.descendantOf(targetNode, node)) return [targetNode];
	          } else if (combinator == 'adjacent') {
	            for (var i = 0, node; node = nodes[i]; i++)
	              if (Selector.handlers.previousElementSibling(targetNode) == node)
	                return [targetNode];
	          } else nodes = h[combinator](nodes);
	        }
	        for (var i = 0, node; node = nodes[i]; i++)
	          if (node == targetNode) return [targetNode];
	        return [];
	      }
	      return (targetNode && Element.descendantOf(targetNode, root)) ? [targetNode] : [];
	    },
	
	    className: function(nodes, root, className, combinator) {
	      if (nodes && combinator) nodes = this[combinator](nodes);
	      return Selector.handlers.byClassName(nodes, root, className);
	    },
	
	    byClassName: function(nodes, root, className) {
	      if (!nodes) nodes = Selector.handlers.descendant([root]);
	      var needle = ' ' + className + ' ';
	      for (var i = 0, results = [], node, nodeClassName; node = nodes[i]; i++) {
	        nodeClassName = node.className;
	        if (nodeClassName.length == 0) continue;
	        if (nodeClassName == className || (' ' + nodeClassName + ' ').include(needle))
	          results.push(node);
	      }
	      return results;
	    },
	
	    attrPresence: function(nodes, root, attr) {
	      if (!nodes) nodes = root.getElementsByTagName("*");
	      var results = [];
	      for (var i = 0, node; node = nodes[i]; i++)
	        if (Element.hasAttribute(node, attr)) results.push(node);
	      return results;
	    },
	
	    attr: function(nodes, root, attr, value, operator) {
	      if (!nodes) nodes = root.getElementsByTagName("*");
	      var handler = Selector.operators[operator], results = [];
	      for (var i = 0, node; node = nodes[i]; i++) {
	        var nodeValue = Element.readAttribute(node, attr);
	        if (nodeValue === null) continue;
	        if (handler(nodeValue, value)) results.push(node);
	      }
	      return results;
	    },
	
	    pseudo: function(nodes, name, value, root, combinator) {
	      if (nodes && combinator) nodes = this[combinator](nodes);
	      if (!nodes) nodes = root.getElementsByTagName("*");
	      return Selector.pseudos[name](nodes, value, root);
	    }
	  },
	
	  pseudos: {
	    'first-child': function(nodes, value, root) {
	      for (var i = 0, results = [], node; node = nodes[i]; i++) {
	        if (Selector.handlers.previousElementSibling(node)) continue;
	          results.push(node);
	      }
	      return results;
	    },
	    'last-child': function(nodes, value, root) {
	      for (var i = 0, results = [], node; node = nodes[i]; i++) {
	        if (Selector.handlers.nextElementSibling(node)) continue;
	          results.push(node);
	      }
	      return results;
	    },
	    'only-child': function(nodes, value, root) {
	      var h = Selector.handlers;
	      for (var i = 0, results = [], node; node = nodes[i]; i++)
	        if (!h.previousElementSibling(node) && !h.nextElementSibling(node))
	          results.push(node);
	      return results;
	    },
	    'nth-child':        function(nodes, formula, root) {
	      return Selector.pseudos.nth(nodes, formula, root);
	    },
	    'nth-last-child':   function(nodes, formula, root) {
	      return Selector.pseudos.nth(nodes, formula, root, true);
	    },
	    'nth-of-type':      function(nodes, formula, root) {
	      return Selector.pseudos.nth(nodes, formula, root, false, true);
	    },
	    'nth-last-of-type': function(nodes, formula, root) {
	      return Selector.pseudos.nth(nodes, formula, root, true, true);
	    },
	    'first-of-type':    function(nodes, formula, root) {
	      return Selector.pseudos.nth(nodes, "1", root, false, true);
	    },
	    'last-of-type':     function(nodes, formula, root) {
	      return Selector.pseudos.nth(nodes, "1", root, true, true);
	    },
	    'only-of-type':     function(nodes, formula, root) {
	      var p = Selector.pseudos;
	      return p['last-of-type'](p['first-of-type'](nodes, formula, root), formula, root);
	    },
	
	    // handles the an+b logic
	    getIndices: function(a, b, total) {
	      if (a == 0) return b > 0 ? [b] : [];
	      return $R(1, total).inject([], function(memo, i) {
	        if (0 == (i - b) % a && (i - b) / a >= 0) memo.push(i);
	        return memo;
	      });
	    },
	
	    // handles nth(-last)-child, nth(-last)-of-type, and (first|last)-of-type
	    nth: function(nodes, formula, root, reverse, ofType) {
	      if (nodes.length == 0) return [];
	      if (formula == 'even') formula = '2n+0';
	      if (formula == 'odd')  formula = '2n+1';
	      var h = Selector.handlers, results = [], indexed = [], m;
	      h.mark(nodes);
	      for (var i = 0, node; node = nodes[i]; i++) {
	        if (!node.parentNode._counted) {
	          h.index(node.parentNode, reverse, ofType);
	          indexed.push(node.parentNode);
	        }
	      }
	      if (formula.match(/^\d+$/)) { // just a number
	        formula = Number(formula);
	        for (var i = 0, node; node = nodes[i]; i++)
	          if (node.nodeIndex == formula) results.push(node);
	      } else if (m = formula.match(/^(-?\d*)?n(([+-])(\d+))?/)) { // an+b
	        if (m[1] == "-") m[1] = -1;
	        var a = m[1] ? Number(m[1]) : 1;
	        var b = m[2] ? Number(m[2]) : 0;
	        var indices = Selector.pseudos.getIndices(a, b, nodes.length);
	        for (var i = 0, node, l = indices.length; node = nodes[i]; i++) {
	          for (var j = 0; j < l; j++)
	            if (node.nodeIndex == indices[j]) results.push(node);
	        }
	      }
	      h.unmark(nodes);
	      h.unmark(indexed);
	      return results;
	    },
	
	    'empty': function(nodes, value, root) {
	      for (var i = 0, results = [], node; node = nodes[i]; i++) {
	        // IE treats comments as element nodes
	        if (node.tagName == '!' || (node.firstChild && !node.innerHTML.match(/^\s*$/))) continue;
	        results.push(node);
	      }
	      return results;
	    },
	
	    'not': function(nodes, selector, root) {
	      var h = Selector.handlers, selectorType, m;
	      var exclusions = new Selector(selector).findElements(root);
	      h.mark(exclusions);
	      for (var i = 0, results = [], node; node = nodes[i]; i++)
	        if (!node._counted) results.push(node);
	      h.unmark(exclusions);
	      return results;
	    },
	
	    'enabled': function(nodes, value, root) {
	      for (var i = 0, results = [], node; node = nodes[i]; i++)
	        if (!node.disabled) results.push(node);
	      return results;
	    },
	
	    'disabled': function(nodes, value, root) {
	      for (var i = 0, results = [], node; node = nodes[i]; i++)
	        if (node.disabled) results.push(node);
	      return results;
	    },
	
	    'checked': function(nodes, value, root) {
	      for (var i = 0, results = [], node; node = nodes[i]; i++)
	        if (node.checked) results.push(node);
	      return results;
	    }
	  },
	
	  operators: {
	    '=':  function(nv, v) { return nv == v; },
	    '!=': function(nv, v) { return nv != v; },
	    '^=': function(nv, v) { return nv.startsWith(v); },
	    '$=': function(nv, v) { return nv.endsWith(v); },
	    '*=': function(nv, v) { return nv.include(v); },
	    '~=': function(nv, v) { return (' ' + nv + ' ').include(' ' + v + ' '); },
	    '|=': function(nv, v) { return ('-' + nv.toUpperCase() + '-').include('-' + v.toUpperCase() + '-'); }
	  },
	
	  matchElements: function(elements, expression) {
	    var matches = new Selector(expression).findElements(), h = Selector.handlers;
	    h.mark(matches);
	    for (var i = 0, results = [], element; element = elements[i]; i++)
	      if (element._counted) results.push(element);
	    h.unmark(matches);
	    return results;
	  },
	
	  findElement: function(elements, expression, index) {
	    if (Object.isNumber(expression)) {
	      index = expression; expression = false;
	    }
	    return Selector.matchElements(elements, expression || '*')[index || 0];
	  },
	
	  findChildElements: function(element, expressions) {
	    var exprs = expressions.join(','), expressions = [];
	    exprs.scan(/(([\w#:.~>+()\s-]+|\*|\[.*?\])+)\s*(,|$)/, function(m) {
	      expressions.push(m[1].strip());
	    });
	    var results = [], h = Selector.handlers;
	    for (var i = 0, l = expressions.length, selector; i < l; i++) {
	      selector = new Selector(expressions[i].strip());
	      h.concat(results, selector.findElements(element));
	    }
	    return (l > 1) ? h.unique(results) : results;
	  }
	});
	
	function $$() {
	  return Selector.findChildElements(document, $A(arguments));
	}
	var Form = {
	  reset: function(form) {
	    $(form).reset();
	    return form;
	  },
	
	  serializeElements: function(elements, options) {
	    if (typeof options != 'object') options = { hash: !!options };
	    else if (options.hash === undefined) options.hash = true;
	    var key, value, submitted = false, submit = options.submit;
	
	    var data = elements.inject({ }, function(result, element) {
	      if (!element.disabled && element.name) {
	        key = element.name; value = $(element).getValue();
	        if (value != null && (element.type != 'submit' || (!submitted &&
	            submit !== false && (!submit || key == submit) && (submitted = true)))) {
	          if (key in result) {
	            // a key is already present; construct an array of values
	            if (!Object.isArray(result[key])) result[key] = [result[key]];
	            result[key].push(value);
	          }
	          else result[key] = value;
	        }
	      }
	      return result;
	    });
	
	    return options.hash ? data : Object.toQueryString(data);
	  }
	};
	
	Form.Methods = {
	  serialize: function(form, options) {
	    return Form.serializeElements(Form.getElements(form), options);
	  },
	
	  getElements: function(form) {
	    return $A($(form).getElementsByTagName('*')).inject([],
	      function(elements, child) {
	        if (Form.Element.Serializers[child.tagName.toLowerCase()])
	          elements.push(Element.extend(child));
	        return elements;
	      }
	    );
	  },
	
	  getInputs: function(form, typeName, name) {
	    form = $(form);
	    var inputs = form.getElementsByTagName('input');
	
	    if (!typeName && !name) return $A(inputs).map(Element.extend);
	
	    for (var i = 0, matchingInputs = [], length = inputs.length; i < length; i++) {
	      var input = inputs[i];
	      if ((typeName && input.type != typeName) || (name && input.name != name))
	        continue;
	      matchingInputs.push(Element.extend(input));
	    }
	
	    return matchingInputs;
	  },
	
	  disable: function(form) {
	    form = $(form);
	    Form.getElements(form).invoke('disable');
	    return form;
	  },
	
	  enable: function(form) {
	    form = $(form);
	    Form.getElements(form).invoke('enable');
	    return form;
	  },
	
	  findFirstElement: function(form) {
	    var elements = $(form).getElements().findAll(function(element) {
	      return 'hidden' != element.type && !element.disabled;
	    });
	    var firstByIndex = elements.findAll(function(element) {
	      return element.hasAttribute('tabIndex') && element.tabIndex >= 0;
	    }).sortBy(function(element) { return element.tabIndex }).first();
	
	    return firstByIndex ? firstByIndex : elements.find(function(element) {
	      return ['input', 'select', 'textarea'].include(element.tagName.toLowerCase());
	    });
	  },
	
	  focusFirstElement: function(form) {
	    form = $(form);
	    form.findFirstElement().activate();
	    return form;
	  },
	
	  request: function(form, options) {
	    form = $(form), options = Object.clone(options || { });
	
	    var params = options.parameters, action = form.readAttribute('action') || '';
	    if (action.blank()) action = window.location.href;
	    options.parameters = form.serialize(true);
	
	    if (params) {
	      if (Object.isString(params)) params = params.toQueryParams();
	      Object.extend(options.parameters, params);
	    }
	
	    if (form.hasAttribute('method') && !options.method)
	      options.method = form.method;
	
	    return new Ajax.Request(action, options);
	  }
	};
	
	/*--------------------------------------------------------------------------*/
	
	Form.Element = {
	  focus: function(element) {
	    $(element).focus();
	    return element;
	  },
	
	  select: function(element) {
	    $(element).select();
	    return element;
	  }
	};
	
	Form.Element.Methods = {
	  serialize: function(element) {
	    element = $(element);
	    if (!element.disabled && element.name) {
	      var value = element.getValue();
	      if (value != undefined) {
	        var pair = { };
	        pair[element.name] = value;
	        return Object.toQueryString(pair);
	      }
	    }
	    return '';
	  },
	
	  getValue: function(element) {
	    element = $(element);
	    var method = element.tagName.toLowerCase();
	    return Form.Element.Serializers[method](element);
	  },
	
	  setValue: function(element, value) {
	    element = $(element);
	    var method = element.tagName.toLowerCase();
	    Form.Element.Serializers[method](element, value);
	    return element;
	  },
	
	  clear: function(element) {
	    $(element).value = '';
	    return element;
	  },
	
	  present: function(element) {
	    return $(element).value != '';
	  },
	
	  activate: function(element) {
	    element = $(element);
	    try {
	      element.focus();
	      if (element.select && (element.tagName.toLowerCase() != 'input' ||
	          !['button', 'reset', 'submit'].include(element.type)))
	        element.select();
	    } catch (e) { }
	    return element;
	  },
	
	  disable: function(element) {
	    element = $(element);
	    element.blur();
	    element.disabled = true;
	    return element;
	  },
	
	  enable: function(element) {
	    element = $(element);
	    element.disabled = false;
	    return element;
	  }
	};
	
	/*--------------------------------------------------------------------------*/
	
	var Field = Form.Element;
	var $F = Form.Element.Methods.getValue;
	
	/*--------------------------------------------------------------------------*/
	
	Form.Element.Serializers = {
	  input: function(element, value) {
	    switch (element.type.toLowerCase()) {
	      case 'checkbox':
	      case 'radio':
	        return Form.Element.Serializers.inputSelector(element, value);
	      default:
	        return Form.Element.Serializers.textarea(element, value);
	    }
	  },
	
	  inputSelector: function(element, value) {
	    if (value === undefined) return element.checked ? element.value : null;
	    else element.checked = !!value;
	  },
	
	  textarea: function(element, value) {
	    if (value === undefined) return element.value;
	    else element.value = value;
	  },
	
	  select: function(element, index) {
	    if (index === undefined)
	      return this[element.type == 'select-one' ?
	        'selectOne' : 'selectMany'](element);
	    else {
	      var opt, value, single = !Object.isArray(index);
	      for (var i = 0, length = element.length; i < length; i++) {
	        opt = element.options[i];
	        value = this.optionValue(opt);
	        if (single) {
	          if (value == index) {
	            opt.selected = true;
	            return;
	          }
	        }
	        else opt.selected = index.include(value);
	      }
	    }
	  },
	
	  selectOne: function(element) {
	    var index = element.selectedIndex;
	    return index >= 0 ? this.optionValue(element.options[index]) : null;
	  },
	
	  selectMany: function(element) {
	    var values, length = element.length;
	    if (!length) return null;
	
	    for (var i = 0, values = []; i < length; i++) {
	      var opt = element.options[i];
	      if (opt.selected) values.push(this.optionValue(opt));
	    }
	    return values;
	  },
	
	  optionValue: function(opt) {
	    // extend element because hasAttribute may not be native
	    return Element.extend(opt).hasAttribute('value') ? opt.value : opt.text;
	  }
	};
	
	/*--------------------------------------------------------------------------*/
	
	Abstract.TimedObserver = Class.create(PeriodicalExecuter, {
	  initialize: function($super, element, frequency, callback) {
	    $super(callback, frequency);
	    this.element   = $(element);
	    this.lastValue = this.getValue();
	  },
	
	  execute: function() {
	    var value = this.getValue();
	    if (Object.isString(this.lastValue) && Object.isString(value) ?
	        this.lastValue != value : String(this.lastValue) != String(value)) {
	      this.callback(this.element, value);
	      this.lastValue = value;
	    }
	  }
	});
	
	Form.Element.Observer = Class.create(Abstract.TimedObserver, {
	  getValue: function() {
	    return Form.Element.getValue(this.element);
	  }
	});
	
	Form.Observer = Class.create(Abstract.TimedObserver, {
	  getValue: function() {
	    return Form.serialize(this.element);
	  }
	});
	
	/*--------------------------------------------------------------------------*/
	
	Abstract.EventObserver = Class.create({
	  initialize: function(element, callback) {
	    this.element  = $(element);
	    this.callback = callback;
	
	    this.lastValue = this.getValue();
	    if (this.element.tagName.toLowerCase() == 'form')
	      this.registerFormCallbacks();
	    else
	      this.registerCallback(this.element);
	  },
	
	  onElementEvent: function() {
	    var value = this.getValue();
	    if (this.lastValue != value) {
	      this.callback(this.element, value);
	      this.lastValue = value;
	    }
	  },
	
	  registerFormCallbacks: function() {
	    Form.getElements(this.element).each(this.registerCallback, this);
	  },
	
	  registerCallback: function(element) {
	    if (element.type) {
	      switch (element.type.toLowerCase()) {
	        case 'checkbox':
	        case 'radio':
	          Event.observe(element, 'click', this.onElementEvent.bind(this));
	          break;
	        default:
	          Event.observe(element, 'change', this.onElementEvent.bind(this));
	          break;
	      }
	    }
	  }
	});
	
	Form.Element.EventObserver = Class.create(Abstract.EventObserver, {
	  getValue: function() {
	    return Form.Element.getValue(this.element);
	  }
	});
	
	Form.EventObserver = Class.create(Abstract.EventObserver, {
	  getValue: function() {
	    return Form.serialize(this.element);
	  }
	});
	if (!window.Event) var Event = { };
	
	Object.extend(Event, {
	  KEY_BACKSPACE: 8,
	  KEY_TAB:       9,
	  KEY_RETURN:   13,
	  KEY_ESC:      27,
	  KEY_LEFT:     37,
	  KEY_UP:       38,
	  KEY_RIGHT:    39,
	  KEY_DOWN:     40,
	  KEY_DELETE:   46,
	  KEY_HOME:     36,
	  KEY_END:      35,
	  KEY_PAGEUP:   33,
	  KEY_PAGEDOWN: 34,
	  KEY_INSERT:   45,
	
	  cache: { },
	
	  relatedTarget: function(event) {
	    var element;
	    switch(event.type) {
	      case 'mouseover': element = event.fromElement; break;
	      case 'mouseout':  element = event.toElement;   break;
	      default: return null;
	    }
	    return Element.extend(element);
	  }
	});
	
	Event.Methods = (function() {
	  var isButton;
	
	  if (Prototype.Browser.IE) {
	    var buttonMap = { 0: 1, 1: 4, 2: 2 };
	    isButton = function(event, code) {
	      return event.button == buttonMap[code];
	    };
	
	  } else if (Prototype.Browser.WebKit) {
	    isButton = function(event, code) {
	      switch (code) {
	        case 0: return event.which == 1 && !event.metaKey;
	        case 1: return event.which == 1 && event.metaKey;
	        default: return false;
	      }
	    };
	
	  } else {
	    isButton = function(event, code) {
	      return event.which ? (event.which === code + 1) : (event.button === code);
	    };
	  }
	
	  return {
	    isLeftClick:   function(event) { return isButton(event, 0) },
	    isMiddleClick: function(event) { return isButton(event, 1) },
	    isRightClick:  function(event) { return isButton(event, 2) },
	
	    element: function(event) {
	      var node = Event.extend(event).target;
	      return Element.extend(node.nodeType == Node.TEXT_NODE ? node.parentNode : node);
	    },
	
	    findElement: function(event, expression) {
	      var element = Event.element(event);
	      return element.match(expression) ? element : element.up(expression);
	    },
	
	    pointer: function(event) {
	      return {
	        x: event.pageX || (event.clientX +
	          (document.documentElement.scrollLeft || document.body.scrollLeft)),
	        y: event.pageY || (event.clientY +
	          (document.documentElement.scrollTop || document.body.scrollTop))
	      };
	    },
	
	    pointerX: function(event) { return Event.pointer(event).x },
	    pointerY: function(event) { return Event.pointer(event).y },
	
	    stop: function(event) {
	      Event.extend(event);
	      event.preventDefault();
	      event.stopPropagation();
	      event.stopped = true;
	    }
	  };
	})();
	
	Event.extend = (function() {
	  var methods = Object.keys(Event.Methods).inject({ }, function(m, name) {
	    m[name] = Event.Methods[name].methodize();
	    return m;
	  });
	
	  if (Prototype.Browser.IE) {
	    Object.extend(methods, {
	      stopPropagation: function() { this.cancelBubble = true },
	      preventDefault:  function() { this.returnValue = false },
	      inspect: function() { return "[object Event]" }
	    });
	
	    return function(event) {
	      if (!event) return false;
	      if (event._extendedByPrototype) return event;
	
	      event._extendedByPrototype = Prototype.emptyFunction;
	      var pointer = Event.pointer(event);
	      Object.extend(event, {
	        target: event.srcElement,
	        relatedTarget: Event.relatedTarget(event),
	        pageX:  pointer.x,
	        pageY:  pointer.y
	      });
	      return Object.extend(event, methods);
	    };
	
	  } else {
	    Event.prototype = Event.prototype || document.createEvent("HTMLEvents").__proto__;
	    Object.extend(Event.prototype, methods);
	    return Prototype.K;
	  }
	})();
	
	Object.extend(Event, (function() {
	  var cache = Event.cache;
	
	  function getEventID(element) {
	    if (element._eventID) return element._eventID;
	    arguments.callee.id = arguments.callee.id || 1;
	    return element._eventID = ++arguments.callee.id;
	  }
	
	  function getDOMEventName(eventName) {
	    if (eventName && eventName.include(':')) return "dataavailable";
	    return eventName;
	  }
	
	  function getCacheForID(id) {
	    return cache[id] = cache[id] || { };
	  }
	
	  function getWrappersForEventName(id, eventName) {
	    var c = getCacheForID(id);
	    return c[eventName] = c[eventName] || [];
	  }
	
	  function createWrapper(element, eventName, handler) {
	    var id = getEventID(element);
	    var c = getWrappersForEventName(id, eventName);
	    if (c.pluck("handler").include(handler)) return false;
	
	    var wrapper = function(event) {
	      if (!Event || !Event.extend ||
	        (event.eventName && event.eventName != eventName))
	          return false;
	
	      Event.extend(event);
	      handler.call(element, event)
	    };
	
	    wrapper.handler = handler;
	    c.push(wrapper);
	    return wrapper;
	  }
	
	  function findWrapper(id, eventName, handler) {
	    var c = getWrappersForEventName(id, eventName);
	    return c.find(function(wrapper) { return wrapper.handler == handler });
	  }
	
	  function destroyWrapper(id, eventName, handler) {
	    var c = getCacheForID(id);
	    if (!c[eventName]) return false;
	    c[eventName] = c[eventName].without(findWrapper(id, eventName, handler));
	  }
	
	  function destroyCache() {
	    for (var id in cache)
	      for (var eventName in cache[id])
	        cache[id][eventName] = null;
	  }
	
	  if (window.attachEvent) {
	    window.attachEvent("onunload", destroyCache);
	  }
	
	  return {
	    observe: function(element, eventName, handler) {
	      element = $(element);
	      var name = getDOMEventName(eventName);
	
	      var wrapper = createWrapper(element, eventName, handler);
	      if (!wrapper) return element;
	
	      if (element.addEventListener) {
	        element.addEventListener(name, wrapper, false);
	      } else {
	        element.attachEvent("on" + name, wrapper);
	      }
	
	      return element;
	    },
	
	    stopObserving: function(element, eventName, handler) {
	      element = $(element);
	      var id = getEventID(element), name = getDOMEventName(eventName);
	
	      if (!handler && eventName) {
	        getWrappersForEventName(id, eventName).each(function(wrapper) {
	          element.stopObserving(eventName, wrapper.handler);
	        });
	        return element;
	
	      } else if (!eventName) {
	        Object.keys(getCacheForID(id)).each(function(eventName) {
	          element.stopObserving(eventName);
	        });
	        return element;
	      }
	
	      var wrapper = findWrapper(id, eventName, handler);
	      if (!wrapper) return element;
	
	      if (element.removeEventListener) {
	        element.removeEventListener(name, wrapper, false);
	      } else {
	        element.detachEvent("on" + name, wrapper);
	      }
	
	      destroyWrapper(id, eventName, handler);
	
	      return element;
	    },
	
	    fire: function(element, eventName, memo) {
	      element = $(element);
	      if (element == document && document.createEvent && !element.dispatchEvent)
	        element = document.documentElement;
	
	      if (document.createEvent) {
	        var event = document.createEvent("HTMLEvents");
	        event.initEvent("dataavailable", true, true);
	      } else {
	        var event = document.createEventObject();
	        event.eventType = "ondataavailable";
	      }
	
	      event.eventName = eventName;
	      event.memo = memo || { };
	
	      if (document.createEvent) {
	        element.dispatchEvent(event);
	      } else {
	        element.fireEvent(event.eventType, event);
	      }
	
	      return event;
	    }
	  };
	})());
	
	Object.extend(Event, Event.Methods);
	
	Element.addMethods({
	  fire:          Event.fire,
	  observe:       Event.observe,
	  stopObserving: Event.stopObserving
	});
	
	Object.extend(document, {
	  fire:          Element.Methods.fire.methodize(),
	  observe:       Element.Methods.observe.methodize(),
	  stopObserving: Element.Methods.stopObserving.methodize()
	});
	
	(function() {
	  /* Support for the DOMContentLoaded event is based on work by Dan Webb,
	     Matthias Miller, Dean Edwards and John Resig. */
	
	  var timer, fired = false;
	
	  function fireContentLoadedEvent() {
	    if (fired) return;
	    if (timer) window.clearInterval(timer);
	    document.fire("dom:loaded");
	    fired = true;
	  }
	
	  if (document.addEventListener) {
	    if (Prototype.Browser.WebKit) {
	      timer = window.setInterval(function() {
	        if (/loaded|complete/.test(document.readyState))
	          fireContentLoadedEvent();
	      }, 0);
	
	      Event.observe(window, "load", fireContentLoadedEvent);
	
	    } else {
	      document.addEventListener("DOMContentLoaded",
	        fireContentLoadedEvent, false);
	    }
	
	  } else {
	    document.write("<script id=__onDOMContentLoaded defer src=//:><\/script>");
	    $("__onDOMContentLoaded").onreadystatechange = function() {
	      if (this.readyState == "complete") {
	        this.onreadystatechange = null;
	        fireContentLoadedEvent();
	      }
	    };
	  }
	})();
	/*------------------------------- DEPRECATED -------------------------------*/
	
	Hash.toQueryString = Object.toQueryString;
	
	var Toggle = { display: Element.toggle };
	
	Element.Methods.childOf = Element.Methods.descendantOf;
	
	var Insertion = {
	  Before: function(element, content) {
	    return Element.insert(element, {before:content});
	  },
	
	  Top: function(element, content) {
	    return Element.insert(element, {top:content});
	  },
	
	  Bottom: function(element, content) {
	    return Element.insert(element, {bottom:content});
	  },
	
	  After: function(element, content) {
	    return Element.insert(element, {after:content});
	  }
	};
	
	var $continue = new Error('"throw $continue" is deprecated, use "return" instead');
	
	// This should be moved to script.aculo.us; notice the deprecated methods
	// further below, that map to the newer Element methods.
	var Position = {
	  // set to true if needed, warning: firefox performance problems
	  // NOT neeeded for page scrolling, only if draggable contained in
	  // scrollable elements
	  includeScrollOffsets: false,
	
	  // must be called before calling withinIncludingScrolloffset, every time the
	  // page is scrolled
	  prepare: function() {
	    this.deltaX =  window.pageXOffset
	                || document.documentElement.scrollLeft
	                || document.body.scrollLeft
	                || 0;
	    this.deltaY =  window.pageYOffset
	                || document.documentElement.scrollTop
	                || document.body.scrollTop
	                || 0;
	  },
	
	  // caches x/y coordinate pair to use with overlap
	  within: function(element, x, y) {
	    if (this.includeScrollOffsets)
	      return this.withinIncludingScrolloffsets(element, x, y);
	    this.xcomp = x;
	    this.ycomp = y;
	    this.offset = Element.cumulativeOffset(element);
	
	    return (y >= this.offset[1] &&
	            y <  this.offset[1] + element.offsetHeight &&
	            x >= this.offset[0] &&
	            x <  this.offset[0] + element.offsetWidth);
	  },
	
	  withinIncludingScrolloffsets: function(element, x, y) {
	    var offsetcache = Element.cumulativeScrollOffset(element);
	
	    this.xcomp = x + offsetcache[0] - this.deltaX;
	    this.ycomp = y + offsetcache[1] - this.deltaY;
	    this.offset = Element.cumulativeOffset(element);
	
	    return (this.ycomp >= this.offset[1] &&
	            this.ycomp <  this.offset[1] + element.offsetHeight &&
	            this.xcomp >= this.offset[0] &&
	            this.xcomp <  this.offset[0] + element.offsetWidth);
	  },
	
	  // within must be called directly before
	  overlap: function(mode, element) {
	    if (!mode) return 0;
	    if (mode == 'vertical')
	      return ((this.offset[1] + element.offsetHeight) - this.ycomp) /
	        element.offsetHeight;
	    if (mode == 'horizontal')
	      return ((this.offset[0] + element.offsetWidth) - this.xcomp) /
	        element.offsetWidth;
	  },
	
	  // Deprecation layer -- use newer Element methods now (1.5.2).
	
	  cumulativeOffset: Element.Methods.cumulativeOffset,
	
	  positionedOffset: Element.Methods.positionedOffset,
	
	  absolutize: function(element) {
	    Position.prepare();
	    return Element.absolutize(element);
	  },
	
	  relativize: function(element) {
	    Position.prepare();
	    return Element.relativize(element);
	  },
	
	  realOffset: Element.Methods.cumulativeScrollOffset,
	
	  offsetParent: Element.Methods.getOffsetParent,
	
	  page: Element.Methods.viewportOffset,
	
	  clone: function(source, target, options) {
	    options = options || { };
	    return Element.clonePosition(target, source, options);
	  }
	};
	
	/*--------------------------------------------------------------------------*/
	
	if (!document.getElementsByClassName) document.getElementsByClassName = function(instanceMethods){
	  function iter(name) {
	    return name.blank() ? null : "[contains(concat(' ', @class, ' '), ' " + name + " ')]";
	  }
	
	  instanceMethods.getElementsByClassName = Prototype.BrowserFeatures.XPath ?
	  function(element, className) {
	    className = className.toString().strip();
	    var cond = /\s/.test(className) ? $w(className).map(iter).join('') : iter(className);
	    return cond ? document._getElementsByXPath('.//*' + cond, element) : [];
	  } : function(element, className) {
	    className = className.toString().strip();
	    var elements = [], classNames = (/\s/.test(className) ? $w(className) : null);
	    if (!classNames && !className) return elements;
	
	    var nodes = $(element).getElementsByTagName('*');
	    className = ' ' + className + ' ';
	
	    for (var i = 0, child, cn; child = nodes[i]; i++) {
	      if (child.className && (cn = ' ' + child.className + ' ') && (cn.include(className) ||
	          (classNames && classNames.all(function(name) {
	            return !name.toString().blank() && cn.include(' ' + name + ' ');
	          }))))
	        elements.push(Element.extend(child));
	    }
	    return elements;
	  };
	
	  return function(className, parentElement) {
	    return $(parentElement || document.body).getElementsByClassName(className);
	  };
	}(Element.Methods);
	
	/*--------------------------------------------------------------------------*/
	
	Element.ClassNames = Class.create();
	Element.ClassNames.prototype = {
	  initialize: function(element) {
	    this.element = $(element);
	  },
	
	  _each: function(iterator) {
	    this.element.className.split(/\s+/).select(function(name) {
	      return name.length > 0;
	    })._each(iterator);
	  },
	
	  set: function(className) {
	    this.element.className = className;
	  },
	
	  add: function(classNameToAdd) {
	    if (this.include(classNameToAdd)) return;
	    this.set($A(this).concat(classNameToAdd).join(' '));
	  },
	
	  remove: function(classNameToRemove) {
	    if (!this.include(classNameToRemove)) return;
	    this.set($A(this).without(classNameToRemove).join(' '));
	  },
	
	  toString: function() {
	    return $A(this).join(' ');
	  }
	};
	
	Object.extend(Element.ClassNames.prototype, Enumerable);
	
	/*--------------------------------------------------------------------------*/
	
	Element.addMethods();


}; // end prototype check block