// assumes /sites/jslib/yui-conventions.js has been loaded
E.onAvailable('name', function () {
  var that = this;
  var suffix = ['cgi', 'jpg', 'gif', 'png'];
  var s = 0;
  var logo = document.createElement('img');
  var alttext = that.firstChild.nodeValue;

  E.addListener(logo, 'load', function () {
    logo.alt = alttext;
    that.replaceChild(logo, that.firstChild);
  });

  E.addListener(logo, 'error', function () {
    s++;
    if (suffix[s]) logo.src = "img/logo."+suffix[s];
  });

  logo.src = "img/logo."+suffix[s];
});