Userland PPP/PPTP tunneling problem

[Brett Glass]

I've got an interesting problem that I'm not sure how to solve. Here's 
the situation. A FreeBSD router is set up to allow a host outside, on the 
Internet, to tunnel into a LAN via PPTP. The router is running PoPToP and 
FreeBSD's userland PPP. The internal LAN uses the addresses 192.168/16, 
and the internal interface of the router is configured with the /16 
subnet mask.

When the client (which is running Windows) connects, it's given a fixed 
IP, specified in the ppp.secret file, corresponding to the user who is 
tunneling in. But the client's routing table has a routing table entry 
that directs packets for 192.168/24 (NOT /16) to the PPTP connection.

I can't find a way to cause userland PPP to tell the Windows client that 
it should be using a different subnet mask. (There's no way to specify 
one in the ppp.secret file.) How is this done?

--Brett Glass