function getXMLHttp(){
	var XMLHttp = null;
	if(window.XMLHttpRequest){
		try{
			XMLHttp = new XMLHttpRequest();
		}catch (e){ }
	}else if(window.ActiveXObject){
		try{
			XMLHttp = new ActiveXObject("Mdxml2.XMLHTTP");
		}catch (e){ 
			try{
				XMLHttp = new ActiveXObject("Microsoft.XMLHTTP");
			}catch (e){ }
		}
	}
	return XMLHttp;
}