function changeImgIn(welcher){
  document.getElementById(welcher).src = "img/topnavi_" + welcher + "_akt.gif";
}
function changeImgOut(welcher){
  document.getElementById(welcher).src = "img/topnavi_" + welcher + ".gif";
}

function drucken(srcsite){
  var optionen ="toolbar=0,location=0,directories=0,status=0,resizable=0,screenY=100,screenX=100,top=100,left=100,width=650,height=500,scrollbars=1";
  window.open(srcsite, "Druckversion", optionen);
}