schaltalt = "0";
function auf(schalter) {
function zu() {
// fuer Netscape 6
if (document.getElementById) {
document.getElementById(schaltalt).style.visibility="hidden";
}
// Ende Netscape 6
if (document.all) {
document.all[schaltalt].style.visibility="hidden";
}
if (document.layers) {
document.layers[schaltalt].visibility="hidden";
}
}
if(schaltalt != "0"){
zu();
}

schaltalt = schalter;
// fuer Netscape 6
if (document.getElementById) {
document.getElementById(schalter).style.visibility="visible";
}
// Ende Netscape 6
if (document.all) {
document.all[schalter].style.visibility="visible";
}
if (document.layers) {
document.layers[schalter].visibility="visible";
}
}

function schliessen(popup) {
// fuer Netscape 6
if (document.getElementById) {
document.getElementById(popup).style.visibility="hidden";
}
// Ende Netscape 6
if (document.all) {
document.all[popup].style.visibility="hidden";
}
if (document.layers) {
document.layers[popup].visibility="hidden";
}
}