function menu(menuNr, totalMenus)
{
    // Hide them all.
    for(i = 0 ; i < totalMenus ; i++) {
        submenu = document.getElementById("menu"+i+"_submenu");

        // But swap the one we want.
        if(i == menuNr) {
            submenu.style.display = submenu.style.display == 'block' ? 'none' : 'block';
        } else {
            submenu.style.display = 'none';
        }
    }
}