[Samba] Winbind and useradd problem on wide network.

[Meli Marco]

Hi all,
I'm using Samba 3.0.2a on Red Hat 9.0 and I have the following problem :

I run Samba with classic script "/usr/local/samba/smbd -D",
"/usr/loca/samba/nmbd -D" and "/usr/local/bin/winbindd -B" when I start the
server, all works fine I can set directory or file permissions in Webmin
"File manager" DOMAINNAME/group-user and the access works fine.
The problem is when I try to insert a local Linux user in "/etc/passwd" file
with any method I know (useradd or by Webmin interface). I' ve notice that
it's take to long time and if I leave run the process it's take also a lot
of memory and all stops.I think it's depend on my large trusted domains
network.I have 15 domains in the world connect by Internet VPN. Also command
like "wbinfo -u/g" returns to you a wide screen of the groups and users
members.
So I can only turn off Winbind, insert Linux user and turn on Winbind again.
Can I limited the winbind query only selected domains ?
Why it is so fast to read informations about users and group but not write
them? (When I restart winbind, also linux users/groups just inserted works
fine ...)    
Can anyone help me ?
Thanks again.
Marco.