function right(e) 
 {
  if (navigator.appName == 'Netscape' && (e.which == 3 || e.which == 2))
   return false;
  else if (navigator.appName == 'Microsoft Internet Explorer' && 
   (event.button == 2 || event.button == 3))
   {
    alert("Leider Pech gehabt");
    return false;
   }
  return true;
 }
document.onmousedown=right;
if (document.layers) window.captureEvents(Event.MOUSEDOWN);
window.onmousedown=right;