// generate a new XMLHTTP Request
function getXmlHttp() {
	if (window.XMLHttpRequest) {
		xmlhttp=new XMLHttpRequest();
	} else if (window.ActiveXObject) {
		xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
	}
	if (xmlhttp == null) {
		alert("Your browser does not support XMLHTTP.");
	}
	return xmlhttp;
}