function auf(unternavi) {

// DOM ALLE NEUEN BROWSER
if (document.getElementById) {
document.getElementById(unternavi).style.visibility="visible";
}

// IE 5

if (document.all) {
document.all[unternavi].style.visibility="visible";
}

// NN 4
if (document.layers) {
document.layers[unternavi].visibility="visible";
}
}

function zu(unternavi) {


if (document.getElementById) {
document.getElementById(unternavi).style.visibility="hidden";
}


if (document.all) {
document.all[unternavi].style.visibility="hidden";
}

if (document.layers) {
document.layers[unternavi].visibility="hidden";
}
}