var imageRollOver = {
  
  main : function() {
    var img = document.images, ipt = document.getElementsByTagName('input'), i, preLoadImg = [];
    // img elements
    for (i = 0; i <img.length; i++) {
      if ((img[i].src.match(/.*_out\./))||(img[i].style.filter)){
        preLoadImg[preLoadImg.length] = new Image;
        preLoadImg[preLoadImg.length-1].src = img[i].src.replace('_out.', '_over.');

        img[i].onmouseover = imageRollOver.over;
        img[i].onmouseout  = imageRollOver.out;
        try {img[i].addEventListener('click', imageRollOver.click, false);}
        catch(e){img[i].attachEvent('onclick', (function(el){return function(){imageRollOver.click.call(el);};})(img[i]));}
      }
    }
    // input[image] elements
    for (i = 0; i <ipt.length; i++) {
      if ((ipt[i].src.match(/.*_out\./))&&(ipt[i].getAttribute('type')=='image')){
        preLoadImg[preLoadImg.length] = new Image;
        preLoadImg[preLoadImg.length-1].src = img[i].src.replace('_out.', '_over.');

        ipt[i].onmouseover = imageRollOver.over;
        ipt[i].onmouseout  = imageRollOver.out;
        try {ipt[i].addEventListener('click', imageRollOver.click, false);}
        catch(e){ipt[i].attachEvent('onclick', (function(el){return function(){imageRollOver.click.call(el);};})(ipt[i]));}
      }
    }
  }
  ,
  
  over : function() {
    var imgSrc, preLoadImgSrc;
    if((this.style.filter)&&(this.style.filter.match(/_out\.gif/)))//(IE5.5-6 && gif)
      this.style.filter = this.style.filter.replace('_out.gif', '_over.gif');
    else
      this.src = this.src.replace('_out.', '_over.');
  },

  out : function(){
    if((this.style.filter)&&(this.style.filter.match(/_over\.gif/)))//(IE5.5-6 && gif)
      this.style.filter = this.style.filter.replace('_over.gif', '_out.gif');
    else
      this.src = this.src.replace('_over.', '_out.');
  },
  
  click : function(){
    if((this.style.filter)&&(this.style.filter.match(/_over\.gif/)))//(IE5.5-6 && gif)
      this.style.filter = this.style.filter.replace('_over.gif', '_out.gif');
    else
      this.src = this.src.replace('_over.', '_out.');
  },

  addEvent : function(){
    try {
      window.addEventListener('load', this.main, false);
    } catch (e) {
      window.attachEvent('onload', this.main);
    }
  }
}

imageRollOver.addEvent();