(function () {
  var onload = function (e) {
    for (var i = 0; i < document.images.length; ++i) {
      if (document.images[i].src.match(/^(.*)_\.([^.]*)$/)) {
        (function (img, pre, ext) {
          var active = new Image(); active.src = pre + '_on.' + ext;
          var normal = new Image(); normal.src = pre + '_.' + ext;
          var onmouseover = function (e) { img.src = active.src; }
          var onmouseout = function (e) { img.src = normal.src; }
          try {
            img.addEventListener('mouseover', onmouseover, false);
            img.addEventListener('mouseout', onmouseout, false);
          }
          catch (e) {
            img.attachEvent('onmouseover', onmouseover);
            img.attachEvent('onmouseout', onmouseout);
          }
        })(document.images[i], RegExp.$1, RegExp.$2);
      }
    }
  }
  try {
    window.addEventListener('load', onload, false);
  }
  catch (e) {
    window.attachEvent('onload', onload);
  }
})()