ipchains masq/forwarding question

Random question for all those well versed in kernel 2.2's ipchains and
masquerading: how do I forward a port from the outside world through the
2.2 masq firewall to another box on the inside LAN? Eg:

<foo.bar.com> --> <firewall> --> <cryastaldragon>

Inside lan is running on the 192.168.1.0/24 net, with the firewall set
as 192.168.1.1. All I'm looking for is a rule that will forward port 80
to crystaldragon.

--
Thomas "Mondoshawan" Tate
mondoshawan@tank.dyndns.org
http://tank.dyndns.org:8080