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