If you want to fix ldapdirectory.py by hand you could add "nestedGroups = []" just above the "if len(result) == 1" line in the restrictedGUIDs( ) method, and make sure the new line is at the same indention as the "if" statement.

This did not resolve the problem on Debian Wheezy with calendarserver 3.2. Having implemented the fix. I get no errors when listing my users like I did before, but users NOT in the group I want to restrict to are still listed. Tobias