if (document.images) {    
  mainon = new Image();      
  mainon.src = "images/mainon.gif";  
  abton = new Image();      
  abton.src = "images/abton.gif";      
  shopon = new Image();      
  shopon.src = "images/shopon.gif";
  eveon = new Image();      
  eveon.src = "images/eveon.gif";
  archon = new Image();      
  archon.src = "images/archon.gif";
  refon = new Image();      
  refon.src = "images/refon.gif";
  delon = new Image();      
  delon.src = "images/delon.gif";
  conton = new Image();      
  conton.src = "images/conton.gif";
  
  mainoff = new Image(); 
  mainoff.src = "images/mainoff.gif"
  abtoff = new Image(); 
  abtoff.src = "images/abtoff.gif"
  shopoff = new Image(); 
  shopoff.src = "images/shopoff.gif"
  eveoff = new Image(); 
  eveoff.src = "images/eveoff.gif"
  archoff = new Image(); 
  archoff.src = "images/archoff.gif"
  refoff = new Image(); 
  refoff.src = "images/refoff.gif"
  deloff = new Image(); 
  deloff.src = "images/deloff.gif"
  contoff = new Image(); 
  contoff.src = "images/contoff.gif"
}

function imgOn(imgName) {
 if (document.images) {
            document[imgName].src = eval(imgName + "on.src");
        }
}

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