[Zope] File objects

[mediaweb@linfe.it]

Sorry my naive question, i am a zope newbie.

According to the zope manual, i should get a file list
of the current folder, using the dtml method:

  <dtml-var standard_html_header>
  <h2><dtml-var title_or_id> <dtml-var document_title></h2>
   <ul>Files
	  <dtml-in expr="objectValues('File')">
	   <li><dtml-var id></li>
	  </dtml-in>
	  </ul>
  </p>
  <dtml-var standard_html_footer>

but i get a blank page, header and footer only are displayed,
even though there are files in folder
(a page refresh has been done, to be safe)

I am using Zope 2.5.1

So, my first question is: what is wrong in the above code?


My second question: can one provide a simple code to all objects 
                    included into a folder?


thank you 


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max