if (document.images) {
  
  image1on = new Image();
  image1on.src = "/images/menu/1_a.gif";
  image1off = new Image();
  image1off.src = "/images/menu/1.gif ";

  image2on = new Image();
  image2on.src = "/images/menu/2_a.gif";
  image2off = new Image();
  image2off.src = "/images/menu/2.gif";
 
  image3on = new Image();
  image3on.src = "/images/menu/3_a.gif";
  image3off = new Image();
  image3off.src = "/images/menu/3.gif";
  
  image4on = new Image();
  image4on.src = "/images/menu/4_a.gif";
  image4off = new Image();
  image4off.src = "/images/menu/4.gif";
  
  image5on = new Image();
  image5on.src = "/images/menu/5_a.gif";
  image5off = new Image();
  image5off.src = "/images/menu/5.gif";
  
  image6on = new Image();
  image6on.src = "/images/menu/6_a.gif";
  image6off = new Image();
  image6off.src = "/images/menu/6.gif";
  
  image7on = new Image();
  image7on.src = "/images/menu/7_a.gif";
  image7off = new Image();
  image7off.src = "/images/menu/7.gif";
  
  image8on = new Image();
  image8on.src = "/images/menu/8_a.gif";
  image8off = new Image();
  image8off.src = "/images/menu/8.gif";
  
  image9on = new Image();
  image9on.src = "/images/menu/9_a.gif";
  image9off = new Image();
  image9off.src = "/images/menu/9.gif";
  
 
}

function changeImages() {

  if (document.images) {

    for (var i=0; i<changeImages.arguments.length; i+=2) {

      document[changeImages.arguments[i]].src = eval(changeImages.arguments[i+1] + ".src");

    }

  }

}

        function isEmpty(str) {
            // Check whether string is empty.
            for (var intLoop = 0; intLoop < str.length; intLoop++)
               if (" " != str.charAt(intLoop))
                  return false;
            return true;
         }