IP maquerading rules

[Steve Doerr <sdoerr@swbell.net>]

Hello.  I hope someone can give me some advice on how to accomplish
something using the ipmasq package.

I'm not sure I'm following how to use the rules system for this.  I want
to open ports 80 and 5432 for my website and it's connection to
postgres.  The server will be running behind my firewall.  I think that
I need to somehow incorporate the following lines into the rules:

ipmasqadm portfw -a -P tcp -L <my_ext_ip> 80 -R <my_int_ClassC_host_ip>
80

ipmasqadm portfw -a -P tcp -L <my_ext_ip> 5432 -R
<my_int_ClassC_host_ip> 5432

Should I just create a Z98apachePG.rul file like below (I'm on 2.2.17
kernel so only ipchains apply)?  Does anyone have a better suggestion?

Thanks very much for any input.
Steve

#######
# Sample rule file
#######

#######
# open Apache and Postgres to the internet through the firewall
case $MASQMETHOD in
ipfwadm)
    $IPFWADM -I -a accept -S 0/0 68 -D 0/0 67 -W eth1 -P tcp
    $IPFWADM -O -a accept -D 0/0 68 -S 0/0 67 -W eth1 -P tcp
    ;;
ipchains)
    $IPCHAINS -A input -j ACCEPT -s 0/0 68 -d 0/0 67 -i eth1 -p tcp
    $IPCHAINS -A output -j ACCEPT -d 0/0 68 -s 0/0 67 -i eth1 -p tcp
    ipmasqadm portfw -a -P tcp -L <my_ext_ip> 80 -R
<my_int_ClassC_host_ip> 80
    ipmasqadm portfw -a -P tcp -L <my_ext_ip> 5432 -R
<my_int_ClassC_host_ip> 5432
    ;;
esac