jsHover = function() {
    var menu = document.getElementById("header");
    if (menu)
    {
        var hEls = menu.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);