active FTP, ipfw and dynamic rules

[Andy Smith]

Hi guys, apologies if this has been discussed before but a couple of
us have been googling and reading man pages for a few hours now and
can't seem to work this one out.

If you've got a machine with IPFW2 and users on it want to use
active FTP, is this possible without doing something like:

ipfw add allow tcp from any 20 to any 1024-65534

??

What I'm trying to duplicate is the functionality of linux iptables
where you would just add something like..

$IPTABLES -A INPUT -i $INET_IFACE -m state --state ESTABLISHED,RELATED -j ACCEPT

and then everything like active FTP would just work.

We don't quite understand how that can be done with ipfw's
keep-state and would appreciate any tips you can offer.

And yes I know that FTP sucks, and that passive FTP can be made to
work, it is just annoying that I cna work this out so easily with
iptables but not with ipfw.

Thanks!