// thanks to  simon willison (http://simon.incutio.com) for following "load" 
// function, and to jeremy keith for sharing it in "DOM scripting"
function addLoadEvent(func) {
  var oldOnLoad = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
    } else {
    window.onload = function () {
      oldOnLoad();
      func();
      }
    }
}