function hiding (fname)
{

if(document.getElementById(fname).style.visibility=="hidden")
{
document.getElementById(fname).style.visibility = "visible";
}
else
{
document.getElementById(fname).style.visibility = "hidden";
}

}

function popup (url) {
 fenster = window.open(url, "Popupfenster", "width=999,height=888,resizable=yes,scrollbars=yes");
 fenster.focus();
 return false;
}