function swapPic()  
{  
if(document.getElementById)  
  {  
  var thePicture='/files/billeder/top/top_forside.jpg';
  if(document.getElementById('topswap')){
      var thePicture=document.getElementById("topswap");  
      var picPath="/Files/Billeder/top/top_"+rnd(3)+".jpg";  
      thePicture.src=picPath;
    }
  }  
}  

function rnd(n)  
{  
return Math.floor(Math.random() * n) + 1;  
}