function vorschau(linkname, windowname,x,y)
{
if (! window.focus)return true;
var href;
if (typeof(linkname) != 'string')
   href=linkname.href;
else
   href=linkname;
window.open(href, windowname,'width='+x+',height='+y+',scrollbars=yes,toolbar=no,menubar=no, resizable');
return false;
}