function sack(file) {
	this.xmlhttp = null;
	this.resetData = function() {
		this.method = "POST";
		this.queryStringSeparator = "?";
		this.argumentSeparator = "&";
		this.URLString = "";
		this.encodeURIString = true;
		this.execute = false;
		this.element = null;
		this.elementObj = null;
		this.requestFile = file;
		this.vars = new Object();
		this.responseStatus = new Array(2);
		this.synchronize = true;
	};
	this.resetFunctions = function() {
		this.onLoading = function() { };
		this.onLoaded = function() { };
		this.onInteractive = function() { };
		this.onCompletion = function() { };
		this.onError = function() { };
		this.onFail = function() { };
		this.onFail = function() { };
	};
	this.reset = function() {
		this.resetFunctions();
		this.resetData();
	};
	this.createAJAX = function() {
		try {
			this.xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e1) {
			try {
				this.xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (e2) {
				this.xmlhttp = null;
			}
		}
		if (! this.xmlhttp) {
			if (typeof XMLHttpRequest != "undefined") {
				this.xmlhttp = new XMLHttpRequest();
			}
			else {
				this.failed = true;
			}
		}
	};
	this.getFormValues = function(formId) {
		var objForm=document.getElementById(formId);
		var formElements=objForm.elements;
	
		for(var i=0; i<formElements.length; i++) {
			if(formElements[i].type && (formElements[i].type=='radio' || formElements[i].type=='checkbox') && formElements[i].checked==false) continue;
			if(formElements[i].disabled && formElements[i].disabled == true) continue;
			var name=formElements[i].name;
			if(name) {
				this.setVar(name, formElements[i].value);
			}
		}
	};
	this.setVar = function(name, value){
		this.vars[name] = Array(value, false);
	};
	this.encVar = function(name, value, returnvars) {
		if (true == returnvars) {
			return Array(encodeURIComponent(name), encodeURIComponent(value));
		}
		else {
			this.vars[encodeURIComponent(name)] = Array(encodeURIComponent(value), true);
		}
	}
	this.processURLString = function(string, encode) {
		encoded = encodeURIComponent(this.argumentSeparator);
		regexp = new RegExp(this.argumentSeparator + "|" + encoded);
		varArray = string.split(regexp);
		for (i = 0; i < varArray.length; i++){
			urlVars = varArray[i].split("=");
			if (true == encode){
				this.encVar(urlVars[0], urlVars[1]);
			}
			else {
				this.setVar(urlVars[0], urlVars[1]);
			}
		}
	}
	this.createURLString = function(urlstring) {
		if (this.encodeURIString && this.URLString.length) {
			this.processURLString(this.URLString, true);
		}
		if (urlstring) {
			if (this.URLString.length) {
				this.URLString += this.argumentSeparator + urlstring;
			}
			else {
				this.URLString = urlstring;
			}
		}
		// prevents caching of URLString
		this.setVar("rndval", new Date().getTime());
		urlstringtemp = new Array();
		for (key in this.vars) {
			if (false == this.vars[key][1] && true == this.encodeURIString) {
				encoded = this.encVar(key, this.vars[key][0], true);
				delete this.vars[key];
				this.vars[encoded[0]] = Array(encoded[1], true);
				key = encoded[0];
			}
			urlstringtemp[urlstringtemp.length] = key + "=" + this.vars[key][0];
		}
		if (urlstring){
			this.URLString += this.argumentSeparator + urlstringtemp.join(this.argumentSeparator);
		}
		else {
			this.URLString += urlstringtemp.join(this.argumentSeparator);
		}
	}
	this.runResponse = function() {
		eval(this.response);
	}
	this.runAJAX = function(urlstring) {
		if (this.failed) {
			this.onFail();
		}
		else {
			this.createURLString(urlstring);
			if (this.element) {
				this.elementObj = document.getElementById(this.element);
			}
			if (this.xmlhttp) {
				var self = this;
				if (this.method == "GET") {
					totalurlstring = this.requestFile + this.queryStringSeparator + this.URLString;
					this.xmlhttp.open(this.method, totalurlstring, this.synchronize);
				}
				else {
					this.xmlhttp.open(this.method, this.requestFile, this.synchronize);
					try {
						this.xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded")
					}
					catch (e) { }
				}
				this.xmlhttp.onreadystatechange = function() {
				switch (self.xmlhttp.readyState) {
					case 1:
						self.onLoading();
					break;
					case 2:
						self.onLoaded();
					break;
					case 3:
						self.onInteractive();
					break;
					case 4:
						self.response = self.xmlhttp.responseText;
						self.responseXML = self.xmlhttp.responseXML;
						self.responseStatus[0] = self.xmlhttp.status;
						self.responseStatus[1] = self.xmlhttp.statusText;
						if (self.execute) {
							self.runResponse();
						}
						if (self.elementObj) {
							elemNodeName = self.elementObj.nodeName;
							elemNodeName.toLowerCase();
							if (elemNodeName == "input" 
								|| elemNodeName == "select"
								|| elemNodeName == "option"
								|| elemNodeName == "textarea") {
							
								self.elementObj.value = self.response;
							}
							else {
								self.elementObj.innerHTML = self.response;
							}
						}
						if (self.responseStatus[0] == "200") {
							self.onCompletion();
						}
						else {
							self.onError();
						}
						self.URLString = "";
					break;
					}
				};
			this.xmlhttp.send(this.URLString);
			}
		}
	};
	this.reset();
	this.createAJAX();
}