[Samba] Seek clarification on use of 'net rpc join -U' to join a NT4 domain

[Dennis]

Dear Friends:

I am trying to join a Suse 9.1 Server running Samba 3.07 to an NT4 
Domain.   One part I am confused about is the command "net rpc join -U" 
... is the username to be used with this command  the name of an 
administrator on the NT4 PDC?  Does that administrator need to be an 
user on the Samba Server and a member of  the "root" group?

I successfully join using the DomainAdmin%Password combo from the NT4 
domain, but with subsequent commands such as "net rpc trustdom list" it 
fails when I enter the password for the DomainAdmin.  What password 
should I be using?

Also the "wbinfo" commands appear to work but I don't understand the 
"wbinfo --set-auth-user" for the same reasons as stated above.  Is the 
user a NT4 DomainAdmin or is it 'root' on the linux box?

My smb.conf follows.  Thank you for your kind help.

Dennis A. Johnson
K.M.B., Inc.
Phoenix, Arizona

# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# smb.conf
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[global]
   workgroup = DOMAIN
   server string = Samba Server
   netbios name = SRVR3
   security = domain
   password server = SRVR1 SRVR2
   wins server = 192.168.0.70
   winbind separator = +
   winbind use default domain = yes
   idmap uid = 15000-20000
   idmap gid = 15000-20000
   use sendfile = yes
   interfaces = 127.0.0.1 eth0
   hosts allow = 192.168.0. 127.
   bind interfaces only = true
   local master = no
   printing = cups
   printcap name = cups
   printer admin = @ntadmin, root, administrator
   disable spoolss = yes
   encrypt passwords = yes
   passdb backend = smbpasswd

[homes]
   comment = Home Directories
   valid users = %S
   browseable = no
   read only = no
   guest ok = no
   printable = no

[Documents]
   comment = Public Documents
   path = /export/Documents
   read only = yes
   writeable = yes
   inherit permissions = yes
   browseable = yes
   guest ok = no

[Pictures]
   comment = Public Pictures
   path = /export/Pictures
   valid users = %S
   read only = no
   writeable = yes
   browseable = yes
   inherit permissions = yes
   guest ok = no

[printers]
   comment = All Printers
   path = /var/spool/samba
   printer admin = root, itadminkmb, dennis
   printable = yes
   create mask = 0600
   browseable = no
   guest ok = no
[print$]
   comment = Printer Drivers
   path = /var/lib/samba/drivers
   write list = @ntadmin root
   force group = ntadmin
   create mask = 0664
   directory mask = 0775
   browseable = yes
   guest ok = no
   printable = no
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# .end. smb.conf
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~