function GetXmlHttpObject()
{
    if (window.XMLHttpRequest)
    {
        // code for IE7+, Firefox, Chrome, Opera, Safari
        return new XMLHttpRequest();
    }

    if (window.ActiveXObject)
    {
        // code for IE6, IE5
        var names = [
            "Msxml2.XMLHTTP.6.0",
            "Msxml2.XMLHTTP.3.0",
            "Msxml2.XMLHTTP",
            "Microsoft.XMLHTTP"
        ];
        
        for(var i in names)
        {
            try
            {
                return new ActiveXObject(names[i]);
            }
            catch(e)
            {
            }
        }
    }

    return null;
}