3rd Party LDAP users in local groups aren't recognized by wiki

Having followed the KB article on setting up wiki webauth to allow 3rd party LDAP users to authenticate (http://support.apple.com/kb/HT4837) I have found that while individual users can be given permissions to access certain wikis, but LDAP users placed into local groups cannot. Is this a bug?

To be more specific:

- Directory Access setup to allow authentication from LDAP server (this works fine for all other services like File Sharing)

- Directions followed in the KB article which basically enables plain text authentication and turns off inline login window (http://support.apple.com/kb/HT4837)

- Local groups created in Server.app -- Accounts -> Groups

- LDAP users placed into those local groups

- Services like file sharing recognize proper permissions based on the groups the LDAP users are in

- Configure a wiki to allow access from a single LDAP user (Gear Icon -> Wiki Settings...) ... this works fine

- Configure a wiki to allow access from the local groups containing LDAP users (again, Gear Icon -> Wiki Settings) ... this appears like it is going to work, but it in fact will fail to give permissions to LDAP users of the respective group upon that user's login. A local user (Server.app -> Accounts -> Users) added to one of these local groups with LDAP people in it works fine and receives proper access to the wiki as expected.

Any ideas before I submit this as a bug?