[Fredrik]

Javascript kanske?

<script LANGUAGE="JavaScript1.1">
<!--
function displayWindow(theURL,winName,width,height,features) { //v3.1
	var theURL = "DINFIL?";
  var window_width = 760;
  var window_height = 470;
  var newfeatures= features;
  var window_top = (screen.height-window_height)/2;
  var window_left = (screen.width-window_width)/2;
  newWindow=window.open(''+ theURL + '',''+ winName + '','width=' + window_width + ',height=' + window_height + ',top=' + window_top + ',left=' + window_left + ',features=' + newfeatures + '');
  newWindow.focus();
}
//-->
</script>

<a href="javascript:displayWindow('DINFIL?','challenge','760','470','')">