Route all traffic through IPSec

Hello,

I'd like to setup an IPSec connection (both sides are m0n0s) between
Subnet1 and Subnet2. Nothing exotic so far.

Now I'd like to route all traffic from Subnet1 (for which m0n0-1 is the
gateway) through the IPSec tunel to m0n0-2 in Subnet2. Even if the
destination is somewhere out in the web.

m0n0-2 then routes all traffic to a Server/Router on Subnet2, which is
again nothing too complicated, as I can simply set it up as the next
gateway.

Now the only complicated part is the middle one, can I and if so any
hints on how do I set up the routing.

Example:
PC01 in Subnet1 opens the browser and surfs to some public website, 
the traffic goes to m0n0-1,
which sends it to m0n0-2, 
which sends it to a server on subnet2,
which then routes it into the internet.

I'm thankful for any advice,
Greetings
 Alexander Schaber