[Zope] Searching File-objects in a Folder

Hi there, For practice I want to implement WikiWiki in Zope. For that, I for one thing have to be able to see if a certain File-object exists in a Folder. What method can I use for that? I tried several from the ZQR, but nothing works. I also have trouble just to get a list of Files in the Folder. Here's a code-fragment of what I try to do in DTML: <dtml-if "Files.getAttributeNode('<dtml-var file>')"> The file <dtml-var file> exists <dtml-else> The file <dtml-var file> does NOT exist </dtml-if> <P> A list of files: <dtml-in "Files.getChildNodes()"> Found: <dtml-var "_['sequence-item']"><br> </dtml-in> So how do I screw up? TIA! RS