var jshover = function()
{
 var menuDiv = document.getElementById("mainmenu")
 if (!menuDiv)
 return;

 var sfEls = menuDiv.getElementsByTagName("li");
 for (var i=0; i<sfEls.length; i++)
 {
 sfEls[i].onmouseover=function()
 {
 this.className+=" jshover";
 }
 sfEls[i].onmouseout=function()
 {
 this.className=this.className.replace(new RegExp(" jshover\\b"), "");
 }
 }
}

if (window.attachEvent)
 window.attachEvent("onload", jshover);