Actually, you need two things in your kernel:

options GATEWAY
options IPFORARDING

the latter of which is mentioned in man 4 options, but is not in the 1.3
GENERIC kernel.. I think they fixed this for 1.3.2, but I'm not sure.. Either
way.. that should fix things up.

You can also flip the value of IPFORWARDING manually with:
sysctl -w net.inet.ip.forwarding=1

I think net.inet.ip.redirect is the key for GATEWAY, can someone confirm this
though?

---
Tim Rightnour    -  root@garbled.net
http://www.zynetwc.com/~garbled/garbled.html