PF & NAT, how to forward GRE?

[Paul Fraser]

Hello list,

I've got a box serving as a router between a wired and wireless network,
as well as providing NAT services for a WAN link to the two
aforementioned systems.

I'd like to forward all incoming GRE traffic on the WAN link to a system
on the wired network. Could anyone advise how?

I thought the PF manual was perhaps a bit vague about forwarding
specific protocols (or for that matter, if it's even possible)...

Cheers,

Paul.