Logging natd translations

[Daniel Eischen]

We need to log all translations from internal IP addresses to
external addresses.  It's good enough to have IPv4 to Ipv4
translations for TCP streams, just one log for the start of
each stream.

We're using FreeBSD-9.1-stable and IPFW with userland natd.
The -log option of natd just seems to log statistics, not
any translation information.  I can't see any easy way to
do this with ipfw's rule log option either.

Any ideas?

-- 
DE