[Samba] Join to AD and different problems

[Miky]

Hi, i have a "strange" situation. I want to use some Linux Box in a AD 
structure using Winbind to access to some shares with user permission. 
I've done correctly on a RH ES 4.0 and i'm using thin machine with no 
problem. I've done the same configuration on a CentOS 4.4 but it doesn't 
run. When i access from a W2K station i have to insert a 
username/password to access on station. On Linux i receive in station 
log (machine name) this messages "reply_spnego:kerberos username 
ShortDomainName\UserName is invalid on this system". I've tried to copy 
same config files (nsswitch, krb5.conf, system-auth,smb.conf) from the 
other machine with no change. I've tested net ads and wbinfo to check if 
comunications with AD is correct, and it seems to be ok. I suppose that 
Kerberes doesn't talk with Winbind but i don't understand what's the 
problem.

thanks