Smoothwall : How to connect to PPTP VPN Server

Say you have a Smoothwall software firewall and a PPTP VPN server running behind it.
You’ll find that, after forwarding all traffic on port 1723 to your server, you won’t be able to connect to it through the internet.
If you edit
and add (at the bottom, right under the “fi”):
ipfwd –masq IP_Address_of_your_PPTP_Server 47 &
For example: ipfwd –masq 47 &
you’ll see it works!
Happy VPN-ning!
Source: Wie kann ich PPTP zu einem internen MS VPN Server forwarden? | Home Page