- Added the "verbose-security" option in zope.conf.

- Changed the Python security policy implementation to emit verbose 
Unauthorized errors when verbose-security is enabled.

- Also, when verbose-security is enabled, computed roles include the 
name of the permission from which the roles were derived, allowing the 
security policy to reliably discover what permission is missing.

- Fixed tests that didn't pass when verbose security was enabled.

- Moved SimpleItem.__repr__ to a more basic class, where it should have 
been all along.

See also:

http://mail.zope.org/pipermail/zope-dev/2005-June/025019.html