if (document.images)
    {
      preload_image_object = new Image();
      // set image url
      image_url = new Array();
      image_url[0] = "/resources/images/index/menu-bg-12.png";
  //  image_url[1] = "";
  //  image_url[2] = "";


       var i = 0;
       for(i=0; i<=3; i++) 
         preload_image_object.src = image_url[i];
    }