jsHover = function() {
  if ( ! document.getElementById("menuLevel3") ) return;
  var hEls = document.getElementById("menuLevel3").getElementsByTagName("LI");
  for ( var i=0, len=hEls.length; i<len; i++ ) {
      hEls[i].onmouseover=function() { this.className+=" jshover"; }
      hEls[i].onmouseout=function() { this.className=this.className.replace(" jshover", "");}
  }
}
if (window.attachEvent && navigator.userAgent.indexOf("Opera")==-1) window.attachEvent("onload", jsHover);