[Zope] Checking if an image exists/simple question

Hi, We have a sql database with employee information. Every employee record has an MWID field. Photo's of the employees are stored in a Zope folder (mwfoto) where the id of every photo has MWID as its name. So we can display the photo like this: <img src="/psychologie/mwfoto/<dtml-var mwid>" This works fine. Now I want to check if a photo exists, and if not, display some other info. In some sort of Zope pseudocode: <dtml if exist(mwid)> showphoto <dtml else> showanotherveryinterestingpicture </dtml-if> How do I do this? Your help is very much appreciated, Henny van der Linde Leiden University linde@fsw.leidenuniv.nl