Radius on server X; VPN on server Y; Samba on server Z

[Sascha Kiefer]

Hi,

I have the following: 
* Radius on server X
* VPN on server Y
* Samba on server Z

Each server is located on a different continent. :-)
Ok, user "foo" now connects to the VPN server and gets authorized by radius.
Fine.
Now, i want him to allow to connect to the samba server. Ideally without
entering
any user+password combination (is that safe enough?); i thought about,
restricting samba connections only
from ip-addresses of the VPN server. But he only is allowed to access his
private
space under samba. He is not alloed to access the space of another user
"bar".
Any hints on that issue?

Thank you.
Sascha