Given the stats from your "ipfstat" I'd guess that you don't have
"options GATEWAY" and/or "options IPFORWARDING" in your kernel, since it
would seem that absolutely no packets are being seen by IP Filter.

Check that forwarding is enabled with "sysctl net.inet.ip.forwarding".
If it's turned off (i.e. "0") then that's definitely going to cause IP
Filter's NAT to do nothing.  You should be able to enable forwarding
without recompiling the kernel though: "sysctl -w net.inet.ip.forwarding=1".

Don't forget to try "ipnat -s" too....

-- 
							Greg A. Woods

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Planix, Inc. <woods@planix.com>; Secrets of the Weird <woods@weird.com>