function setupMenus() {
    var is_rtl = $(document.body).getStyle('direction') == 'rtl';
    $$('a.menu-item').each(function(item) {
        var sub_item = $(item.get('id').replace(/menu_item/,'sub_menu'));
        if (sub_item) {
            item.addEvents({
                'mouseenter': function(ev) {
                    var item_coords = item.getCoordinates();
                    var sub_coords = sub_item.getCoordinates();
                    if (is_rtl) {
                        left_pos = item_coords.right-sub_coords.width;
                    }
                    else {
                        left_pos = item_coords.left;
                    }
                    sub_item.setStyles({ 'visibility':'visible', 'left': left_pos+'px', 'top':item_coords.bottom+'px' });
                },
                'mouseleave': function(ev) {
                    ev = new Event(ev);

                    if (!$(ev.relatedTarget).hasClass('sub-menu-item')) {
                        sub_item.setStyle('visibility', 'hidden');
                    }
                }
            });
            sub_item.addEvent('mouseleave', function(ev) { sub_item.setStyle('visibility','hidden') });
        }
    });
}