samba - Nov 2003 - Network Browsing Therory

Hello all,

I am a fanatic user of samba3 but there is still one thing I get troubles 
with it : network browsing.

Here's the scenario : Suppose we have 3 domains (A B C) on 3 different IP 
subnets on 3 different LAN.
Pdcs of domain A and B are samba 3, Domain C is NT4sp6
Domain C PDC is also a wins server and all clients / servers of all domains 
are configured to register their names on it.
Users in domain C can browse all the domains.
Users in domains A and B only see their domain.

The question is : How can I make users in domains A and B browse other 
domains ?

Of course samba 3 pdcs are also domain master, local master and configured 
tu use the wins server.

Any input ?

Thanks a lot,
Stef