var showroom = new Image();
showroom.src="img/nav/showroom_a.gif";

var showroomoff = new Image();
showroomoff.src="img/nav/showroom.gif";

var search = new Image();
search.src="img/nav/search_a.gif";

var searchoff = new Image();
searchoff.src="img/nav/search.gif";

var contact_us = new Image();
contact_us.src="img/nav/contact_us_a.gif";

var contact_usoff = new Image();
contact_usoff.src="img/nav/contact_us.gif";

var warranty = new Image();
warranty.src="img/nav/warranty_a.gif";

var warrantyoff = new Image();
warrantyoff.src="img/nav/warranty.gif";

var find = new Image();
find.src="img/nav/find_a.gif";

var findoff = new Image();
findoff.src="img/nav/find.gif";

function on(imgname, action)
{
if(action)
  {
   eval ('document.'+imgname+'.src = '+imgname+'.src')
   }
else eval ('document.'+imgname+'.src = '+imgname+'off.src');
}