On Tue, 20 Sep 2005 10:47:58 +0100
  Nik Clayton <nik at ngo dot org dot uk> wrote:

> And done.  And now it works.  Thank you very much for the help.

> I'm a bit confused about why it's working though.  I've definitely 
>configured the m0n0wall PPTP server to listen on 192.168.0.239.  I'm 
>a bit confused about the traffic flow.

> If I've configued my VPN client (it's the built in one on Mac OS X) 
>to connect to 192.168.2.1, how does it then reach the PPTP server 
>that's running on .0.239?

That is easy, but it requires some analogies that will kill the 
purists.  Think of the PPTP server is sort of a virtual router.  It 
listens on all the interfaces, but it's has a "gateway" at .239 which 
is where you come out.  You can not see .239 until you connect, since 
it is on the far side or the "router."  Clear as mud? :-)