RMI works in one direction in VPN

Hi!

We have two machines /A/ and /B/, both with access to the public
Internet but due to the lack of static IP of /B/ we are using VPN. /A/
plays the role of /VPN server/, whereas /B/ is /VPN client/. We runned
Java RMI-application (JADE agent system) working inside of VPN as
client-server application.

The application works fine when application server stands on /A/, and
application client on /B/. The situation changes when trying the
opposite. Machine /A/ constantly *refuses the connection* to machine
/B/ ("connection timed out", see stack trace at:
http://tinyurl.com/erck2).

/A/ is Linux-based, whereas /B/ is Windows-xp-based. Network analyzer
shows that in both cases there is a traffic from /A/ to /B/ and from
/B/ to /A/. Below are LOG files of Ethereal Network Analyzer) from the
latter case, when the things go wrong (B:app-client -> A:app-server):

captured at A side: http://tinyurl.com/hwpu3
captured at B side: http://tinyurl.com/k32oq

Also pinging from B to A works fine. Here are VPN configuration files
for:

A:vpn-server: http://tinyurl.com/jsqyy
B:vpn-client: http://tinyurl.com/e5geq

Any suggestion what could be wrong ?

Regards,

Maciej