function YerDegis(el,which) {  el.src=el.getAttribute(which || "origsrc");}
function YerDegisSetup() {  var x = document.getElementsByTagName("img");
  for (var i=0;i<x.length;i++){    var oversrc = x[i].getAttribute("oversrc");
    if (!oversrc) continue;
    x[i].oversrc_img = new Image();
    x[i].oversrc_img.src=oversrc;
    x[i].onmouseover = new Function("YerDegis(this,'oversrc');");
    x[i].onmouseout = new Function("YerDegis(this);");
    x[i].setAttribute("origsrc",x[i].src);}}
var PreYerDegisOnload =(window.onload)? window.onload : function(){};
window.onload = function(){PreYerDegisOnload(); YerDegisSetup();}