function getHTTPObject() {
    if (typeof XMLHttpRequest != 'undefined') {
	return new XMLHttpRequest();
    }
    try {
	return new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e) {
	try {
	    return new ActiveXObject("Microsoft.XMLHTTP");
	} catch (e) {}
    }
    return false;
}

var xmlhttp = getHTTPObject();