I already have a pptp connection with two firewalls, one as a server and one as a client.
Now my problem is that i dont know how to configure the rules and the network addreses in both firewalls in order to connect both networks in each side of the tunnel.
IPSec is preferred, as it does all the routing for you.
That said, you can do it with PPTP.
knowledge base article KB62479 documents the process.
Remember to use a unique subnet for the PPTP addresses the PPTP server hands out, to avoide routing issues when the link goes down.