I have below code...why it is not working in firefox. I can see req object 
created in firefox too but it never goes to the onreadystatechange event and 
I can not see the alert ("hello")

-->

<script language="javascript">
var req;
function loadXMLDoc(url) {
 req = false;
    // branch for native XMLHttpRequest object
    if(window.XMLHttpRequest) {
     try {
   req = new XMLHttpRequest();
        } catch(e) {
   req = false;
        }
    // branch for IE/Windows ActiveX version
    } else if(window.ActiveXObject) {
        try {
         req = new ActiveXObject("Msxml2.XMLHTTP");
       } catch(e) {
         try {
            req = new ActiveXObject("Microsoft.XMLHTTP");
         } catch(e) {
            req = false;
         }
  }
    }
 if(req) {
  req.onreadystatechange = processReqChange();
  req.open("GET", url, true);
  req.send("");
 }
}

function processReqChange()
{
    if (req.readyState==4)
        alert("hello");
}

loadXMLDoc("http://www.microsoft.com");

</script>