var status = false;
var image = " ";
var image2 = " ";
var index = 0;
   
function rollover(image, image2, index)
 {
   if(status==false)
   {
   document.images[index].src=image;
   status=true;
   }
   
   else
   {
   document.images[index].src=image2;
   status=false;
   }
 }