jQuery().ready(function () {
    var items = document.getElementById("menu").getElementsByTagName("li");
    for (var i = 0; i < items.length; i++) {
        items[i].onmouseover = function () {
            el = $(this);
            el.addClass("hover");
            $('ul:first', this).css('visibility', 'visible');
        }
        items[i].onmouseout = function () {
            el = $(this);
            el.removeClass("hover");
            $('ul:first', this).css('visibility', 'hidden');
        }
    }
});