var IW= 0;
var IH= 0;
var PX= 0;
var PY= 0;
var us= null;
var tab = null;
var zelle = null;
var b= null;
var browoffset = 0;
function navposition() {
 
 b = document.getElementsByTagName("body")[0];
 
	if (navigator.appName != "Microsoft Internet Explorer")  browoffset = - 18; 
	us = document.getElementById("p2nnav");
	  
      if (us != null){       
        IH= b.clientHeight;
        IW= b.clientWidth;                
		tab = document.getElementById("tabelle");
		zelle = document.getElementById("zelle");
		PX= tab.offsetLeft + zelle.offsetLeft;
        if (b.scrollLeft>PX) PX=b.scrollLeft;        		
        PY = (IH+b.scrollTop- us.offsetHeight) + browoffset;
        if (PY > zelle.offsetTop + us.offsetHeight )
			PY = zelle.offsetTop + us.offsetHeight;        
        us.style.top= PY;
        us.style.left= PX;
        us.style.display= "";
		us.style.width="500px";
      }
  
 }
setInterval("navposition()",200);