function popupVenster(url, titel, breedte, hoogte, offset, scrollbars)
{
	window.open(url, titel, "height=" + hoogte + ",toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=" + scrollbars + ",resizable=1,width=" + breedte + ",top=" + offset + ",left=" + offset);
}