[Zope] Calling a method with an unusual name.

I am forced to name all my zope methods with the extension .dtml because M$ word refuses to save the files in WebDAV unless they have an extension. This creates a problem when I try to call a python expression from DTML: <dtml-var "something.dtml"> comes back with "global name something not found". How do I call documents with an extension? example: <dtml-var "phys_petoverview2.dtml()">