function check_ajax(pfad,pid,sid)
{

var xmlHttpObject = false;
var bv = 0;

if (typeof XMLHttpRequest != 'undefined')
{
    xmlHttpObject = new XMLHttpRequest();
    bv=1;
}
if (!xmlHttpObject)
{
    try
    {
        xmlHttpObject = new ActiveXObject("Msxml2.XMLHTTP");
        bv=2;
    }
    catch(e)
    {
        try
        {
            xmlHttpObject = new ActiveXObject("Microsoft.XMLHTTP");
            bv=3;
        }
        catch(e)
        {
            xmlHttpObject = null;
        }
    }
}

if (bv>0){
var dataURL=pfad+"?p=" + pid + "&s=" + sid + "&t=" + bv;
xmlHttpObject.open("GET", dataURL, true);
xmlHttpObject.send(null);
} else {
document.images['js'].src = document.images['js'].src+'?p='+pid+'&s='+sid;
}

}