status is zero in chrome and firefox

See more:

Javascript

XML

REST

I have to call Rest Services using javascript. My code is:

function CreateXMLHttpRequest() {
         if (typeof XMLHttpRequest != "undefined") {

             return new XMLHttpRequest();
         }
         else if (typeof ActiveXObject != "undefined") {

             return new ActiveXObject("Microsoft.XMLHTTP");
         }
         else {
             throw new Error("XMLHttpRequestnot supported");
         }
     }
     function CallWebService() {
        objXMLHttpRequest = CreateXMLHttpRequest();
       objXMLHttpRequest.open("POST", "http://www.rest.net/services/abc.svc/json/GetXml", true);
       objXMLHttpRequest.setRequestHeader("Content-Type", "application/xml;charset=UTF-8");
         var packet = '<?xml version="1.0" encoding="utf-8" ?><CompanyRequest xmlns="http://schemas.datacontract.org/2004/07/abc.DomainModel" xmlns:i="http://www.w3.org/2001/XMLSchema-instance"><CompanyName>company</CompanyName></CompanyRequest>';
         objXMLHttpRequest.onreadystatechange = function () {

             if (objXMLHttpRequest.readyState == 4&&objXMLHttpRequest.status==200) {

                alert(objXMLHttpRequest.responseText);
             }
         }
         objXMLHttpRequest.send(packet);
     }

status is 200 in IE and i am able to get response. But in firefox and Chrome the status is 0. How can i overcome this problem suggest me...and also how can i parse this response

Thanks in advance....