function qRollover() {
  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('qroll')!=-1){
      imgSrc[i]=imgarr[i].getAttribute('src');
      imgClass[i]=imgarr[i].className;
      imgPreload[i]=new Image();
      if (imgClass[i].match(/qroll (\S+)/)) {
        imgPreload[i].src = imgClass[i].match(/qroll (\S+)/)[1]
      }
      imgarr[i].setAttribute('xsrc', imgSrc[i]);
      imgarr[i].onmouseover=function(){
        this.setAttribute('src',this.className.match(/qroll (\S+)/)[1])
      }
      imgarr[i].onmouseout=function(){
        this.setAttribute('src',this.getAttribute('xsrc'))
      }
    }
  }
}
qRollover();