samba - Nov 2003 - Linux-clients how to connect/auth on samba?

hi list (or people inside)

i've got a server running with samba 3.0 on linux. i have all my clients
dual-boot, meaning win and linux installed on them.

my samba-server is configured as pdc, with auth.method=smbpasswd.

All works fine with my win-clients. I get connected, authenticated and
executed all login-scripts! -> nearly perfect!

But: linux-clients:
- i do: net join -s SERVER -U root, enter my password and get
"Successfully joined Domain DOMAIN".
- afterwards, i log out and try to login in the form:
DOMAIN\user with the accomodate password from smbpasswd.

Result: Authentification failure

i configured nsswitch.conf and entered the lines concerning winbind into
smb.conf. but still: same messages.

Does anybody have:
- Linux clients, connecting and authenticating on a Samba PDC
- perhaps also executing some login-scripts to have the shares on a
per-user-base

...or is it even easier to do with ldap???? or whats wrong??
what do you need to help??

thx in advance