function openPopup(url,width,height) {
  top.name = "popup";
  var popup = window.open(url,"neuesFenster",'toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=1,resizable=1,width='+width+',height='+height);
  if( navigator.appName.substring(0,8) == "Netscape" ) {
    popup.location = url;
    popup.opener = self;
  }
 }
 
 function showMapItem(id) {
  for (var i = 1; i <= 20; i++) closeMapItem('map'+i);
  document.getElementById(id).style.display = "block";
}

function closeMapItem(id) {
  if (document.getElementById(id)) document.getElementById(id).style.display = "none";
}