How to grant samba share access for a particular group?

Issue

• All users accounts have been added to the TEST+GSS.NET group in the AD domain.

• The client-specific log file [client IP address].log has this part:

  [2009/07/30 15:40:19, 3] lib/util_sid.c:string_to_sid(223) 
    string_to_sid: Sid TEST+GSS.NET does not start with 'S-'. 
  [2009/07/30 15:40:19, 2] smbd/service.c:make_connection_snum(616) 
    user 'COG+dstoner-test' (from session setup) not permitted to access this share (db) 
  [2009/07/30 15:40:19, 3] smbd/error.c:error_packet_set(106) 
    error packet at smbd/reply.c(514) cmd=117 (SMBtconX) NT_STATUS_ACCESS_DENIED