Tunneled file sharing server - server

[Michael Hipp]

I have 2 servers (both Red Hat 9) separated by the Internet. There are 
Win users on both sides enjoying Samba. I need to share a folder on 
ServerB with the users on ServerA ...


PC ----- ServerA ---------- ServerB ----- PC
     SMB           Internet  Folder   SMB

ServerB will have a folder to be used by both PC groups.

What should I use for a secure "tunnel" between the two servers? Tunnel 
needs to be self sustaining 24x7 and invisible to the users.

Would NFS be a good way to make the shared folder available to ServerA 
and then share it with Samba? Can NFS and Samba work with the same 
directory and not collide?

I don't want to just tunnel the SMB ports because that makes *all* 
shared folders visible on both sides.

Any help appreciated,
Michael Hipp