[Samba] require_membership_of being ignored?

[Peter Capazzi]

I'm running into the same issue that Mike posted about.
 
I've got authentication working as well as the auto creation of home
directories. The problem is anybody that has a valid domain account can
come in regardless of group. 
 
I'm running SuSE
The require_membership_of parameter supposed to be in the auth section
right? 
 
The common-auth file I have is:
auth    required        pam_env.so
auth    sufficient      pam_unix2.so
auth    required        pam_winbind.so use_first_pass
require_membership_of=DOMAINNAME\groupname
 
I've tried with an account that is explicitly outside of the group and
that users account is allowed in.