samba - Feb 2005 - Error joining W2000 to samba domain server

Hi list,

I'm a newbie, from Catalunya, Spain, sorry in advance for my english... ;-)

I try to join diferents W2000 workstations (and one wXP) to a domain
suplied by samba (3.0.7), the first w2000 and the wXP success without
errors (I can enter a domain, logon diferents users in the same computer
with own profiles, and maps diferents drives correctly) but the nexts
W2000 clients reports this error when type the username and pass (root) to
enter a domain:

"the suplied credentials enter in conflict with others entered before"
       (my traduction from spanish, original: "las credenciales
suministradas entran en conflicto con otras entradas
anteriormente")

The steps I follow before:

- Create a machine account in Samba box: adduser -g MYGROUP -d /dev/null
-s /dev/null MACHINENAME$

- Create a samba machine account: smbpasswd -a -m MACHINENAME

- Create a samba root acccount: smbpasswd -a root


Anyone can help me? I read a lot documentation, my brain it's burning like
a hell! ;-)

Thanks.