function createRequestObject() {
  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;
      }
    }
  }
  return req;
}