ajax xmlhttp.onreadystatechange function
===

I have this code:

    function loadRegions()
    {
        var xmlhttp;

        if (window.XMLHttpRequest)
        {// code for IE7+, Firefox, Chrome, Opera, Safari
             xmlhttp=new XMLHttpRequest();
        }
        else
        {// code for IE6, IE5
             xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
        }
  
        xmlhttp.onreadystatechange=function()
        {
            if (xmlhttp.readyState==4 && xmlhttp.status==200)
            {
               alert("Ready:"+xmlhttp.status);
               xmlDoc=xmlhttp.responseXML;
               x=xmlDoc.getElementsByTagName("region");
               alert(x[0]);
               alert(x[1]);
           }
       }
 
       var ctrcode = frm.elements['countrycode'];
       xmlhttp.open("GET","http://mydomain.gr/regionslist.php?countrycode="+ctrcode.value,true);
       xmlhttp.send();
    }

I have a select item im my html and when someone selects an item then this function is called to get the regions of this country. So i can see from my console that the request is done,but the response is never gotten. My onreadystatechange function is never called.When i delete xmlhttp.status==200 then the function is called but the xmlDoc object is null and xmlhttp.status==0. The url i use works if i call it alone. So why my onreadystatechange does not work and why it does not return status 200.
