samba - Oct 2013 - Rights Issues - one user getting: "Primary group is 0 and contains 0 supplementary groups" on standalone server

Greetings,

We are having some rights issues on Samba 3.6.18 running on Slackware64 
14.0 (the official Slackware Package).  One of our users is having 
access issues and I believe I have traced the problem to the following 
entry in the log.smbd:

  Primary group is 0 and contains 0 supplementary groups

Issuing the groups command for this user returns the 8 Linux groups in 
which the user has membership.

In researching this, I found another reference to this log entry for 
which the solution had to do with Windows groups and their relationship 
to local groups.

Since we are using Samba stand-alone, we do not create any Windows 
groups and use local Linux groups for privileges. (I'm assuming Samba 
can still be used this way.)

My question is: How does Samba calculate these group memberships?

I'll look through the source code and see what I can see, but I am no 
programming wizard, so I doubt I'll find what I need there.

Thanks!
Stu...

P.S. My apologies if this gets posted to the list twice: I accidentally 
tried sending it *before* I subscribed again. Oops!

-- 
Stuart Reedy               Working hard for a great university!
stu at coe.uky.edu
859 257-7966               http://www.coe.uky.edu/~stu/