function openDisclaimer() 
{
   var url      = 'http://www.tiw.eu/popup_disclaimer.asp'
   var height   = 275;
   var width    = 600;
   var name     = "Disclaimer";
   var left     = Math.floor( (screen.width - width) / 2);
   var top      = Math.floor( (screen.height - height) / 2);   
   var winParms = "top=" + top + ",left=" + left + ",height=" + height + ",width=" + width;
   winParms    += ",status=no,toolbar=no,menubar=no,location=no,scrollbars=no";   
   var win      = window.open(url, name, winParms);
   return;
}