if (document.getElementById) {
    document.write('<style type="text/css">\n')
    document.write('.submenu{display: none;}\n')
    document.write('</style>\n')
}

function SwitchMenu(obj) {
    if(document.getElementById) {
        var el = document.getElementById(obj);
        var ar = document.getElementById("masterdiv").getElementsByTagName("span"); 
        if(el.style.display != "block") {
            for (var i=0; i<ar.length; i++) {
                if (ar[i].className=="submenu")
                    ar[i].style.display = "none";
            }
            el.style.display = "block";
        } else {
            el.style.display = "none";
        }
    }
}