if (document.images) {
   aboutOn = new Image();
   aboutOn.src = "/images/header/nav/about_us_on.gif";
   
   transdermalOn = new Image();
   transdermalOn.src = "/images/header/nav/transdermal_on.gif";
   
   componentOn = new Image();
   componentOn.src = "/images/header/nav/component_on.gif";
   
      
   aboutOff = new Image();
   aboutOff.src = "/images/header/nav/about.gif";
   
   transdermalOff = new Image();
   transdermalOff.src = "/images/header/nav/transdermal.gif";
   
   componentOff = new Image();
   componentOff.src = "/images/header/nav/component.gif";
   
}


function swapImage(imgName,newImage) {
   if (document.images) {
      eval('document.' + imgName + '.src = ' + newImage + '.src');
   }
}