smbd calls initgroups() to set the unix group members
of the existing process and then getgroups() to get the
list back. This is truncated to the OS limit (NGROUPS_MAX).
So the NT_USER_TOKEN (built by the net_sam_logon reply) can
have more groups than those listed in unix_user token.
2.2. solved this by calling add_supplementary_nt_login_groups()
See also bug 267
this is an OS limitation and not much we can do about it. Closing it.
originally reported against 3.0.0beta3. CLeaning out
non-production release versions.