abouton = new Image(135,42);
  abouton.src='images/about_on.jpg';
  aboutoff = new Image(135,42);
  aboutoff.src='images/about_off.jpg';
  
  activityon = new Image(97,42);
  activityon.src='images/activity_on.jpg';
  activityoff = new Image(97,42);
  activityoff.src='images/activity_off.jpg';
  
  siteon = new Image(118,42);
  siteon.src='images/site_on.jpg';
  siteoff = new Image(118,42);
  siteoff.src='images/site_off.jpg';
  
  exploreon = new Image(107,42);
  exploreon.src='images/explore_on.jpg';
  exploreoff = new Image(107,42);
  exploreoff.src='images/explore_off.jpg';
  
  stuffon = new Image(124,42);
  stuffon.src='images/stuff_on.jpg';
  stuffoff = new Image(124,42);
  stuffoff.src='images/stuff_off.jpg';
  
  moreon = new Image(138,42);
  moreon.src='images/more_on.jpg';
  moreoff = new Image(138,42);
  moreoff.src='images/more_off.jpg';
  
function lightup(imgName)
 {
   if (document.images)
    {
      imgOn=eval(imgName + "on.src");
      document.images[imgName].src= imgOn;
    }
 }

function turnoff(imgName)
 {
   if (document.images)
    {
      imgOff=eval(imgName + "off.src");
      document.images[imgName].src= imgOff;
    }
 }