function createXMLHTTPRequest() {
    var request = false;
    try {
        request = new XMLHttpRequest(); /* Firefox */
    }
    catch (err1) 
    {
        try {
            request = new ActiveXObject('Msxml2.XMLHTTP'); // some IE's
        }
        catch (err2) {
            try {
                request = new ActiveXObject('Microsoft.XMLHTTP'); // some IE's
            }
            catch (err3) {
                request = false;
            }
        }
    }
    return request;
} // end getXMLHTTPRequest