function domRollover() {
   if (navigator.userAgent.match(/Opera (\S+)/)) {
      var operaVersion = parseInt(navigator.userAgent.match(/Opera (\S+)/)[1]);
   }
   if (!document.getElementById||operaVersion <7) return;
   var imgarr=document.getElementsByTagName('img');
   var imgPreload=new Array();
   var imgSrc=new Array();
   var imgClass=new Array();
   for (i=0;i<imgarr.length;i++){
      if (imgarr[i].className.indexOf('domroll')!=-1){
         imgSrc[i]=imgarr[i].getAttribute('src');
         imgClass[i]=imgarr[i].className;
         imgPreload[i]=new Image();
         if (imgClass[i].match(/domroll (\S+)/)) {
            imgPreload[i].src = imgClass[i].match(/domroll (\S+)/)[1]
         }
         imgarr[i].setAttribute('xsrc', imgSrc[i]);
         imgarr[i].onmouseover=function(){
            this.setAttribute('src',this.className.match(/domroll (\S+)/)[1])
         }
         imgarr[i].onmouseout=function(){
            this.setAttribute('src',this.getAttribute('xsrc'))
         }
      }
   }
}
domRollover();