if (top.frames.length==0)
 {
  document.write("<frameset framespacing=\"0\" border=\"false\" frameborder=\"0\" rows=\"98,*\">");
   document.write("<frame name=\"Banner\" target=\"Oben\" src=\"../html/top.htm\" scrolling=\"no\" noresize marginheight=\"0\" marginwidth=\"0\">");
   document.write("<frameset cols=\"206,*\">");
    document.write("<frame name=\"Inhalt\" src=\"../html/nav.htm\" target=\"Navigation\" scrolling=\"no\" noresize topmargin=\"0\" marginwidth=\"1\">");
    document.write("<frame name=\"Hauptframe\" src=" + seite_aktuell + " scrolling=\"auto\" noresize target=\"_self\">");
   document.write("</frameset>");
   document.write("<noframes>");
   document.write("<a href=\"../noframes.htm\"></a>");
   document.write("</noframes>");
  document.write("</frameset>");
  document.frames["Hauptframe"].location.href=seite_aktuell;
}