[Zope] all DTML Methods of current folder and subfolder

Hi! I have a dtml method in a folder which should display all "document_title"s of all "DTML Method"s in the current folder and all sub folders! (should work as navigation frame) How can I do that? I tried <dtml-in "Info.objectValues(['DTML Method'])"> where "Info" is the current folder where the method itself is stored but that didn't work ... :-( any suggestions? tia Wolfgang