[Samba] domain groups in samba 2.2.3a debian woody

[Mindsweep Support]

Hello, I'm using samba 2.2.3a in debian woody.  I've set up the debian server as a PDC, and clients can join and log in fine.  What I'm now looking for is how to set up groups for my users.  When I try to set the security for a file in windows, I see the users on the linux server, but no groups.  How do I map between unix group and samba groups?  I've seen mention of the "domain groups" and "domain group map" parameters, but both throw errors with testparm.  What do I do?

Thanks