[Zope] List subfolders within any folder

Hi *, I'm having problems with a relatively easy task. I have a DTML Method which contains: <dtml-in expr="objectValues('Folder')" sort="title" skip_unauthorized> <li><a href="&dtml-absolute_url;"><dtml-var title_or_id></a></li> </dtml-in> Which when I "view" on it's own happily lists the folders within my root folder. Yet somehow when I reference this object with another DTML Document, it list nothing?! Any help appreciated. Regards, Michael