[Zope] newbie question

[Barry Drake]

I'm getting an error in CMFCore.utils in the
_mergedLocalRoles function.  The error is:

Exception Type  TypeError
Exception Value can only concatenate tuple (not
"list")    
                to tuple

I modify utils.py, after saving a copy, in order to
obtain diagnostic output.  Then I delete utils.pyc,
after saving a copy, in order to force a recompile
(even used compilezpy.py for this a couple of times). 
Zope never seems to use the new version.

Also, I added comments ahead of the line where the
error occurs so that the line number should be higher
than the original error line number.  But, it's always
the same.

I suspect that I have a fundamental misunderstanding
of how Zope uses code in the Products directory.  

Is Zope storing all the compiled byte code in the
data.fs file?  Is there a way to force Zope to use new
code?

Also, the previous developer removed the Control Panel
putting Plone as the root of everything.  How can I
get information that the Control Panel usually
provides?

System: Zope 2.7.1, Plone 2.0.5, Python 2.3.4, Red Hat
7.2

Thank you.

Barry Drake

The traceback:

Traceback (innermost last):
  Module ZPublisher.Publish, line 101, in publish
  Module ZPublisher.mapply, line 88, in mapply
  Module ZPublisher.Publish, line 39, in call_object
  Module
Products.CMFFormController.ControllerPageTemplate,
line 80, in __call__
  Module
Products.CMFFormController.BaseControllerPageTemplate,
line 39, in _call
  Module Products.CMFFormController.ControllerBase,
line 243, in getNext
  Module
Products.CMFFormController.Actions.TraverseTo, line
36, in __call__
  Module ZPublisher.mapply, line 88, in mapply
  Module ZPublisher.Publish, line 39, in call_object
  Module
Products.CMFFormController.ControllerPythonScript,
line 159, in __call__
  Module Shared.DC.Scripts.Bindings, line 306, in
__call__
  Module Shared.DC.Scripts.Bindings, line 343, in
_bindAndExec
  Module Products.PythonScripts.PythonScript, line
323, in _exec
  Module None, line 19, in pag_edit
   - <ControllerPythonScript at /Plone/pag_edit used
for /Plone/Members/bldrake/privLinks.pag>
   - Line 19
  Module Products.CMFDefault.Document, line 192, in
edit
  Module Products.CMFCore.CMFCatalogAware, line 69, in
reindexObject
  Module Products.CMFCore.CatalogTool, line 262, in
reindexObject
  Module Products.CMFCore.CatalogTool, line 235, in
catalog_object
  Module Products.ZCatalog.ZCatalog, line 528, in
catalog_object
  Module Products.ZCatalog.Catalog, line 381, in
catalogObject
  Module Products.PluginIndexes.common.UnIndex, line
240, in index_object
  Module
Products.PluginIndexes.KeywordIndex.KeywordIndex, line
61, in _index_object
  Module
Products.PluginIndexes.KeywordIndex.KeywordIndex, line
94, in _get_object_keywords
  Module Products.CMFCore.CatalogTool, line 63, in
allowedRolesAndUsers

THE FOLLOWING ERROR SHOULD BE ON LINE 216 NOW, BUT
HASN'T MOVED FROM THE ORIGINAL.

  Module Products.CMFCore.utils, line 215, in
_mergedLocalRoles
TypeError: can only concatenate tuple (not "list") to
tuple