function loadXMLDocAsyncTest(url,readyFunc,postData) {
    if (window.XMLHttpRequest) {// code for IE7+, Firefox, Chrome, Opera, Safari
        xmlhttp=new XMLHttpRequest();
    } else {// code for IE6, IE5
        xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
    }
    xmlhttp.open(!!postData?"POST":"GET", url, true);
    xmlhttp.onreadystatechange = function() {
        readyFunc(xmlhttp);
    };

    if (!!postData && typeof postData == "string")
        xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded");

    xmlhttp.send(!!postData?postData:null);
}