In article <54676.213.65.133.73.1127740686.squirrel@webmail.antisocial.nu>,
	"Jonathan" <phonic@antisocial.nu> writes:
>> Is the a.b.c.d there the interface (address) on which the packet
>> arrives?
> Yes. tun0.

That can be achieved with IPFilter's or PF's "fastroute" statement.
I'm a bit rusty on this command because I used it a long time ago
but IIRC it work like this:

fastroute to tun0 from a.b.c.d to any

Please refer to "man ipf.conf" or man "pf.conf" for more details.

	Kind regards

-- 
Matthias Scheler                                  http://scheler.de/~matthias/