NetBSD-5.0.2/dist/ipf/FWTK/README

There are two patch files in this directory, each allowing for the Firewall
Toolkit to be used in a transparent proxy configuration.

ftp-gw.diff	- A patch written by myself for use only with IP Filter and
		  ftp-gw from the Firewall Toolkit.  You need to copy ip_nat.h,
		  ip_fil.h and ip_compat.h to the ftp-gw directory to compile
		  once this patch has been applied.

fwtkp		- A set of patches written by James B. Croall (jcroall@foo.org)
		  for use with both IP Filter and ipfwadm (for Linux) and more
		  of the various FWTK gateway plugins, including:
		  ftp-gw http-gw plug-gw rlogin-gw tn-gw

Both patches when applied to the Firewall toolkit require the same
configuration for IP Filter.

Darren