Bridge the two interface

From:	Tommaso Di Donato <tommaso dot didonato at gmail dot com>
To:	m0n0wall at lists dot m0n0 dot ch
Subject:	Bridge the two interface
Date:	Tue, 12 Jul 2005 10:20:46 +0200

Hi all.
I would like to know how to bridge the two interface: my goal is to
create a filtering bridge..
If I understood well, this is possible, right? I saw that I have a
"bridge" option only if I add an optional interface.. but I do not
understand how it works.. Do I have to create a new "opt" interface,
just to bridge lan and wan?
TIA
Tom