I have a little problem:

My Windows-Box is behind a Linux-Box (Mandrake 9.1 and iptables). Thelinux-box is the gateway for all windows-boxes.
On the windows-box (IP: I have installed BorderManager
3.7 R2.

When I try to connect to a VPN-Server (outside of my LAN - over the
Internet) I can connect, but no crypted packets were received.

When I use a dial-up connection to the internet direct on the
(AVM-Fritz-card) the vpn-connect works fine.

So, can anyone help me which port I have to forward to my windows-box
?? And
how I can do this (with iptables)

This would be great,

thank you.