function getHTTPObject() {
  var xmlhttp;
   if(window.XMLHttpRequest){
      // Firefox, Safari, Opera...
      xmlhttp = new XMLHttpRequest();
   } else if(window.ActiveXObject) {
      // Internet Explorer 5+
      xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
   } else {
      // There is an error creating the object,
      // just as an old browser is being used.
      alert('Problem creating the XMLHttpRequest object');
   }
   return xmlhttp;
}