samba - Oct 2005 - problem with winbind I think !?

Hi,
I have some error into my log.winbind and I can't 
understand why.
[2005/10/03 16:38:28, 2]
nsswitch/winbindd_pam.c:winbindd_pam_auth_crap(654)
   NTLM CRAP authentication for user [D-CH-CAI3]\[] 
returned
NT_STATUS_NO_SUCH_US
ER (PAM: 4)
[2005/10/03 16:38:38, 2]
nsswitch/winbindd_pam.c:winbindd_pam_auth_crap(654)
   NTLM CRAP authentication for user [D-CH-CAI3]\[] 
returned
NT_STATUS_NO_SUCH_US
ER (PAM: 4)
[2005/10/03 16:38:43, 2]
nsswitch/winbindd_pam.c:winbindd_pam_auth_crap(654)
   NTLM CRAP authentication for user [D-CH-CAI3]\[] 
returned
NT_STATUS_NO_SUCH_US
ER (PAM: 4)

and all the wbinfo test is working, and the ntlm_auth is 
working too.

any clue what that mean ?

thanks in advance.

regards,
arno