Permissions for group shares

[Willis Ralph]

I am running OpenVMS V7.3-2 with Samba version  2.2.8

The product is up and running and has been added to an NT Active
directory as a member node with no issues. 
The problems are to do with security. We set up the security to use
"Domain security".Personal or home shares are fine and easy to set up.
The issue is really with group shares. On a UNIX based samba
installation this is straight forward as UNIX has multiple groups and
the share security can be easily administered by assigning users to the
relevant groups in order to access to a group share. The problem is that
VMS doesn't have this same idea of groups as UNIX. I have thought about
using a resource identifier that can be used via ACLs to "own" the
share. The users can be granted the resource identifier in question and
the "valid users" list in SAMBA can have the resource identifier as its
valid user. 
The bottom line is that SAMBA doesn't seem to respect ACLs ,they don't
seem to work. It could be that I am not approaching this problem in the
most sensible way. Any guidance would be appreciated.

Regards
Willis