function mouseOver(id, disp){
  if(!disp || disp != '1')return;
  var obj = document.getElementById(id);
  if (!obj) return;
  
  var imgUrl = obj.src;
  imgUrl = imgUrl.replace('_on','');
  var index = imgUrl.lastIndexOf('.');
  if (index < 0 ) return false;
  
  var src = imgUrl.substring(0, index);
  var extension = imgUrl.substring(index);
  src += "_on";

   obj.src =  src + extension;
}

function mouseOut(id, disp){
  if(!disp || disp != '1')return;
  var obj = document.getElementById(id);
  if (!obj) return;

  var imgUrl = obj.src;
  
  imgUrl = imgUrl.replace('_on','');
  obj.src =  imgUrl;
}

function swapImg(obj, url){
  if(!obj) return;
  
  if(obj.src)obj.src = url;
}