function getXhr(){
	var xhr = null; 
	if(window.XMLHttpRequest) // Firefox and others
		xhr = new XMLHttpRequest(); 
	else 	if(window.ActiveXObject){ // Internet Explorer 
				try {
					xhr = new ActiveXObject("Msxml2.XMLHTTP");
				} catch (e) {
					xhr = new ActiveXObject("Microsoft.XMLHTTP");
				}
			}
			else { // XMLHttpRequest is not supported by the clients Browser 
				alert("Your Browser do not accept the XMLHTTPRequest objets..."); 
				xhr = false; 
			} 
	return xhr
}