      sfHover = function() {
        var sfEls = document.getElementById("nav_main").getElementsByTagName("LI");
        for (var i=0; i<sfEls.length; i++) {
          sfEls[i].onmouseover = function() {
            this.className += " sfhover";
          }
          sfEls[i].onmouseout = function() {
            this.className=this.className.replace(new RegExp(" sfhover\\b"), "");
          }
        }
      }
      if (window.attachEvent) window.attachEvent("onload", sfHover);