function fenster(url)
{
 xpos=(screen.availWidth-800)/2;
 ypos=(screen.availHeight-600)/2;
 F1= window.open(url,"produktFrame","scrollbars=no,width=800,height=600,status=no,menubar=no,toolbar=no,resize=no");
 F1.moveTo(xpos,ypos);
 F1.focus();
}

function swap(Bildname,BildURL)
{
document.images[Bildname].src = BildURL;
}