function toggleVisibility(id, NNtype, IEtype, WC3type) {
    if (document.getElementById) {
        eval("document.getElementById(id).style.visibility = \"" + WC3type + "\"");
    } else {
        if (document.layers) {
            document.layers[id].visibility = NNtype;
        } else {
            if (document.all) {
                eval("document.all." + id + ".style.visibility = \"" + IEtype + "\"");
            }
        }
    }
}