var theOffset = 195;
var theWidth = '628px';
 
function trueheight() {
 if (window.innerHeight) {
  return window.innerHeight;
 } else if (document.body && document.documentElement.clientHeight) {
  return document.documentElement.clientHeight;
 } else {
  return 0;
 }
}
 
function anpassen() {
 var fhoehe = trueheight() - theOffset;
 //alert(fhoehe);
 try {
  $('theiframe').setStyle({
   'height' : fhoehe + 'px',
   'width' : theWidth
  });
 } catch(err) {
  void(0);
 }
}