function getAjaxRequest() {
  var obj = _getXMLHttpObject();
  if ( obj == void 0 ) {
    alert("Ajax is not supported!");
  }
  return eval("new "+obj);
}

function isAjaxSupported() {
  var obj = _getXMLHttpObject();

  return (obj != void 0);
}

function _getXMLHttpObject() {
  if (typeof XMLHttpRequest != "undefined") {
    return "XMLHttpRequest()";
  }
  else if (typeof ActiveXObject != "undefined") {
    var versions = ["MSXML2.XmlHttp.6.0","MSXML2.XmlHttp.3.0"];
    var version = void 0;
    for (var i=0; i < versions.length; i++) {
      try {
        new ActiveXObject(versions[i]);
        version = versions[i];
        break;
      } 
      catch (oError) {                
      }
    } 
    if (version != void 0) {
      return "ActiveXObject(\""+version+"\")";
    }
  } 
  return void 0;
}