Authentication for user [root] -> [root] FAILED with error NT_STATUS_WRONG_PASSWORD

Salut à tous,
Je suis nouveau sous Linux et Debian. J'ai un gros problème avec SaMBa. Il est bien installé, il fonctionne correctement je pense, mais je ne peux pas joindre mon domaine.

Je l'ai installé en PDC, ça fonctionne, les machines se ping, je vois les partages depuis ma machines XP Pro SP2, mais impossible de joindre le domaine. Pourtant, le registre Windows a correctement été modifié...
Extrait du fichier log.nmbd
[2005/07/16 18:22:24, 0] nmbd/nmbd.c:main(668)
Netbios nameserver version 3.0.14a-Debian started.
Copyright Andrew Tridgell and the Samba Team 1994-2004
[2005/07/16 18:22:25, 2] nmbd/nmbd.c:main(692)
Becoming a daemon.
Bla bla bla...
[2005/07/16 18:22:25, 0] nmbd/nmbd_logonnames.c:add_logon_names(163)
add_domain_logon_names:
Attempting to become logon server for workgroup OLINET on subnet 192.168.1.2
[2005/07/16 18:22:25, 2] nmbd/nmbd_logonnames.c:become_logon_server(136)
become_logon_server: Atempting to become logon server for workgroup OLINET on subnet 192.168.1.2
Bla bla bla...
[2005/07/16 18:22:25, 0] nmbd/nmbd_logonnames.c:become_logon_server_success(124)
become_logon_server_success: Samba is now a logon server for workgroup OLINET on subnet UNICAST_SUBNET
[2005/07/16 18:22:25, 2] nmbd/nmbd_become_dmb.c:become_domain_master_stage1(173)
become_domain_master_stage1: Becoming domain master browser for workgroup OLINET on subnet UNICAST_SUBNET
[2005/07/16 18:22:25, 0] nmbd/nmbd_become_dmb.c:become_domain_master_stage2(113)
*****
Samba server SERVEUR is now a domain master browser for workgroup OLINET on subnet UNICAST_SUBNET
*****
Bla bla bla...
[2005/07/16 18:22:31, 2] nmbd/nmbd_elections.c:send_election_dgram(41)
send_election_dgram: Sending election packet for workgroup OLINET on subnet 192.168.1.2
Bla bla bla...
[2005/07/16 18:22:33, 0] nmbd/nmbd_become_dmb.c:become_domain_master_stage2(113)
*****
Samba server SERVEUR is now a domain master browser for workgroup OLINET on subnet 192.168.1.2
*****
Bla bla bla...
[2005/07/16 18:22:40, 2] nmbd/nmbd_elections.c:run_elections(201)
run_elections: >>> Won election for workgroup OLINET on subnet 192.168.1.2
Bla bla bla...
*****
Samba name server SERVEUR is now a local master browser for workgroup OLINET on subnet 192.168.1.2
*****
Bla bla bla...

Lorsque je tente une jonction au domaine depuis XP en tant que root, j'ai le message suivant sur ma machine XP Pro : "L'erreur suivante c'est produite lors de la tentative de jonction au domaine 'olinet':
Echec d'ouverture de session : nom d'utilisateur inconnue ou mot de passe incorrect.

Et voila ce que j'obtient dans le fichier de log sous Debian:
Extrait du fichier /var/log/samba/log.devstudio (la machine xp)
[2005/07/16 19:17:40, 2] auth/auth.c:check_ntlm_password(312)
check_ntlm_password: Authentication for user [root] -> [root] FAILED with error NT_STATUS_WRONG_PASSWORD
[2005/07/16 19:17:40, 2] smbd/server.c:exit_server(609)
Closing connections
[2005/07/16 19:17:40, 2] lib/access.c:check_access(324)
Allowed connection from (192.168.1.4)
[2005/07/16 19:17:40, 2] smbd/server.c:exit_server(609)
Closing connections
[2005/07/16 19:17:40, 2] auth/auth.c:check_ntlm_password(312)
check_ntlm_password: Authentication for user [root] -> [root] FAILED with error NT_STATUS_WRONG_PASSWORD
[2005/07/16 19:17:40, 2] smbd/server.c:exit_server(609)
Closing connections

Pourtant "root" a bien un compte samba (smbpasswd -a root) et il n'est pas en "invalid users".

Mon fichier smb.conf

###############################################################
# #
# #
# MON FICHIER SAMBA DE TEST #
# #
# #
###############################################################

####SECTION GLOBAL####
[global]

#Definition du nom du serveur
netbios name = serveur
workgroup = olinet
server string = %h SaMBa %v sur Debian Sarge

#Parametres du controleur de domain
domain master = yes
domain logons = yes
local master = yes
preferred master = yes
os level = 65
wins support = yes
time server = yes
name resolve order = host wins bcast
logon script = logonscript.bat
logon home = \\serveur\%U

hosts allow = 192.168.1.0/24 127.0.0.1
hosts deny = 0.0.0.0/0
interfaces = eth0, lo
bind interfaces only = yes

#Debug
log file = /var/log/samba/log.%m
max log size = 1000
log level = 2
syslog = 3
syslog only = no

#Gestion des comptes - Authentication
security = user
username map = /etc/samba/smbusers

encrypt passwords = true
passdb backend = tdbsam guest
obey pam restrictions = yes
guest account = invite
dns proxy = no

unix password sync = yes
smbpasswd file = /etc/samba/smbpasswd
unix password sync = yes

passwd program = /usr/bin/passwd %u
passwd chat = *Enter\snew\sUNIX\spassword:* %n\n *Retype\snew\sUNIX\spassword:* %n\n .
pam password change = yes

#Ajout
add user script = /usr/sbin/useradd -g smbuser -s /bin/false
add machine script = /usr/sbin/useradd -d /dev/null -M -g 1001 -s /bin/false %u

# Do something sensible when Samba crashes: mail the admin a backtrace
panic action = /usr/share/samba/panic-action %d

#DIVERS
# Visualisation des fichiers
hide dot files = yes

# Respect de la casse
case sensitive = no
default case = lower
preserve case = yes
short preserve case = no

socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192

###################### Definitions des partages ########################
[homes]
comment = Repertoire de %U
volume = mon disque
invalid users = invite
browseable = no
writeable = yes
create mask = 0700
directory mask = 0700

[netlogon]
path = /home/samba/netlogon/
locking = no
writeable = no
public = no
browseable = no

[public]
comment = Repertoire public
path = /home/public/
guest ok = yes
read only = yes

Mon fichier smbusers
olivier = olivier
root = administrateur administrator admin

Désolé pour ce long post.
Merci d'avance pour votre aide à tous

Tux