var bigpicWin = null;

function showbigimage(url, picwidth, picheight, bildunterschrift)
{
  if (!bigpicWin || bigpicWin.closed)
  {
    // Zur Positionierung des Fensters wird die Bildschirmauflösung ermittelt
    // und damit die XY-Position der linken oberen Ecke berechnet

    usrwidth = screen.width;
    usrheight = screen.height;

    winwidth = picwidth;
    winheight = picheight;

    var X = (usrwidth - winwidth) / 2;
    var Y = (usrheight - winheight) / 2;

    properties = "toolbar=no,location=no,directories=no,status=no,scrollbars=no,resizable=no,copyhistory=no,width="+winwidth+",height="+winheight+",";

    checkie = navigator.appName.indexOf("icrosoft");
    if (checkie == -1)
    {
      properties = properties+"screenX="+X+",screenY="+Y;
    }
    else
    {
      properties = properties+"left="+X+",top="+Y;
    }
    bigpicWin = window.open('','bigpicWin',properties);

    bigpicWin.document.open();
    bigpicWin.document.write('<HTML>\n<HEAD>\n');
    bigpicWin.document.write('<TITLE>'+bildunterschrift+'</TITLE>\n');
    bigpicWin.document.write('</HEAD>\n');
    bigpicWin.document.write('<BODY MARGINWIDTH="0" MARGINHEIGHT="0" LEFTMARGIN="0" TOPMARGIN="0" BOTTOMMARGIN="0" oncontextmenu="return false">\n');
    bigpicWin.document.write('<A HREF="JavaScript:self.close()"><IMG src="'+url+'" HSPACE="0" VSPACE="0" BORDER="0" ALT="'+bildunterschrift+'"></A>\n');
    bigpicWin.document.write('</BODY>\n');
    bigpicWin.document.write('</HTML>\n');
    bigpicWin.document.close()

    bigpicWin.focus();
  }
  else
  {
    bigpicWin.focus();
  }
}
function menu(Ereigniss) {
alert(" Gesperrt "); 
return false;
}
