Falcon 4 internet connection problem

A friend and I are having difficulty connecting to each other in multiplayer
in Falcon 4.

We both have the same build of the software (unpatched).

He is connected to the internet directly, I am trying to connect using a
gateway connection and a direct connection with no luck.

Both of us are running XP, additional firewalls to XP's own are turned off,
the game has been 'unblocked' by XP's firewall, IP addresses are correct
etc.

Any pointers appreciated.

Binky.

Not really sure why we can't see each other. LAN multiplayer works fine.