how to prevent smbd to set the netbios name as domain? Hi samba experts

I have a stupid question maybe. Looking into the code around the:

http://cvs.opensolaris.org/source/xref/sfw/usr/src/cmd/samba/samba-3.0.25a/source/smbd/sesssetup.c#489

I can see the samba "giving up" set the netbios name as the name of the 
domain. It leads to domain\\users are not authenticated in cifs member 
server (samba).

Is there a option setting the domain name explicitly? (similar to 
netbios name)

Why the domain name is not taken from the ream option?

Here is configuration and log.smbd digest:

adsdc - ADS DC (w2k3)
wxptst - WinXP testing client
s10-sp - smbd winbind running solaris10@SPARC

-------- log.smbd ----------
[2007/06/27 13:25:14, 5] lib/util.c:(287)
   Netbios name list:-
   my_netbios_names[0]="S10-SP"
...
[2007/06/27 13:25:15, 10] passdb/pdb_get_set.c:(604)
   pdb_set_domain: setting domain S10-SP, was

Regards

Jiri

