[Samba] Samba, NetBSD, and mapping groups

[Ken Cross]

Samba works well with NetBSD, but many of the more advanced/useful
features don't work.  In particular, winbind doesn't work (because
NetBSD lacks nsswitch support) and winbind via PAM doesn't work because
NetBSD doesn't support PAM.

I can map domain users in a reasonable fashion using "add user script"
and "username map" as necessary.  

My problem is mapping domain groups.  Winbind isn't available, and I
can't figure out how to enable "groupname map" (or "domain group map")
-- it appears to have been de-supported.

Any suggestions how to support domain groups without winbind?

Thanks,
Ken