function SimpleSwap(el,which) {
  el.src=el.getAttribute(which || "origsrc");
}
function SimpleSwapSetup() {
  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("SimpleSwap(this,'oversrc');");
    x[i].onmouseout = new Function("SimpleSwap(this);");
    x[i].setAttribute("origsrc",x[i].src);
  }
}
var PreSimpleSwapOnload =(window.onload)? window.onload : function(){};
window.onload = function(){PreSimpleSwapOnload(); SimpleSwapSetup();}