function createXMLHttp () {
	if (typeof XMLHttpRequest != "undefined") {
		return new XMLHttpRequest();					
	} else if (window.ActiveXObject) {
		var aVersions = ["MSXML2.XMLHttp.5.0", "MSXML2.XMLHttp.4.0", "MSXML2.XMLHttp.3.0", "MSXML2.XMLHttp", "Microsoft.XMLHttp"];
		for (var i = 0; i <  aVersions.length; i++) {
			try {
				var oXmlHttp = new ActiveXObject(aVersions[i]);
				return oXmlHttp;
			} catch (err) {}
		}
	}
	throw new Error("XMLHttp object could not be created.");
}

function postRequest(url, formName, handler) {
	objXMLHttp = createXMLHttp();
	objXMLHttp.open("GET", getUniqueURL(url), true);				
	objXMLHttp.onreadystatechange = handler;
	objXMLHttp.send (null);
}

function getUniqueURL(url) {
	var date = new Date();
	url += "&date=" + date.getTime();
	return url;
}