Dual wan configuration

[ronoz]

Hello,
I have installed Zentyal server and would like to configure it as a dual wan gateway.
This is not a standard dual wan configuration because it's not 2 internet connection but one internet connection and the second is a network of a company I receive services from which is not connected to the internet.
I started configuring the server but soon enough I've noticed that Zentyal does not refer to the second connection as a gateway since it is not connected to the internet, it displayed as "linked" but does not even show up an IP address.
Today I have 2 separate networks while each computer has 2 NICs and route commands to send the traffic to some specific IP addresses to the second network.
My goal is to configure the server to make the routes between the networks so it will be transparent to the computers.
I would also like to be able to connect via VPN to the server to use the second network from other locations.
Is this configuration possible and how do I do it?
Thanks

[ronoz]

Anyone?

[christian]

I was first tempted to answer to your initial post but reading it again and again, I realize I even don't understand what your landscape is made of neither what you intend to achieve. I'm perhaps getting too old