[Samba] Add winbind user to local unix group?

[Sledz, Steffen]

I wan't to add some winbind authorized domain users to the local unix
group "uucp" to give them access to some test equipment connected to
serial ports (e.g. using minicom). I tried to add their UIDs
(10000...) to the uucp item in /etc/group, but this does not seem to
work. "id -G" reports just the group memberships from the domain.
What's the right way to configure this?

The local machine is running openSUSE 11.0, is not a DC and does not
run a local samba server.