DSL and IPChains

[Brian <lxy@antares.cloudnet.com>]

There's been some postings over the last few days of a similar nature to
my problem.  Let's say I have a /29 for my DSL.  220.220.220.8/29 sounds
good (since I don't know the actual IPs at this point).  I'll be setting
up a linux box with 3 NICs, one for the router and the other two will have
masqueraded subnets.  So I have something like this:

Cisco 675 ip=220.220.220.14 s/n=255.255.255.248
eth0 ip=220.220.220.13 s/n=255.255.255.248 gate=220.220.220.14
eth1 ip=192.168.1.254 s/n=255.255.255.0 gate=220.220.220.13
eth2 ip=192.168.2.254 s/n 255.255.255.0 gate=220.220.220.13

I want to have a couple of my masqueraded stations accesible by an outside
IP address.  How do I set up IPchains to forward, say, 220.220.220.12 to
192.168.1.4?  I'm sure I've seen it done, but I don't know the syntax.
Any ideas??  TIA!!

-Brian