jsHover = function() {
    var hEls = document.getElementById('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);
}