Here's a copy of the /etc/firewall.user in use on Kamikaze 7.06. I generally comment out ports 22, 80 and 8100 just to keep things a bit more secure.
WRT54GL v1.0 Kamikaze 7.06
WHR-HP-G54 Kamikaze 7.06
#!/bin/sh
# Copyright (C) 2006 OpenWrt.org
iptables -F input_rule
iptables -F output_rule
iptables -F forwarding_rule
iptables -t nat -F prerouting_rule
iptables -t nat -F postrouting_rule
# The following chains are for traffic directed at the IP of the
# WAN interface
iptables -F input_wan
iptables -F forwarding_wan
iptables -t nat -F prerouting_wan
# DMZ outgoing
iptables -A forwarding_rule -i eth0.2 -o eth0.1 -j ACCEPT
iptables -A forwarding_rule -i eth0.2 -o eth0.0 -j ACCEPT
### Open port to WAN
## -- This allows port 22 to be answered by (dropbear on) the router
iptables -t nat -A prerouting_wan -p tcp --dport 22 -j ACCEPT
iptables -A input_wan -p tcp --dport 22 -j ACCEPT
## -- This allows port 80 to be answered by (dropbear on) the router
iptables -t nat -A prerouting_wan -p tcp --dport 80 -j ACCEPT
iptables -A input_wan -p tcp --dport 80 -j ACCEPT
### Port forwarding
## -- This forwards port 8100 on the WAN to port 80 on 192.168.1.100
iptables -t nat -A prerouting_wan -p tcp --dport 8100 -j DNAT --to 192.168.1.100:80
iptables -A forwarding_wan -p tcp --dport 80 -d 192.168.1.100 -j ACCEPT
## -- This forwards ports 5060-5061 on the WAN to 192.168.1.100
iptables -t nat -A prerouting_wan -p udp --dport 5060:5061 -j DNAT --to 192.168.1.100
iptables -A forwarding_wan -d 192.168.1.100 -j ACCEPT
### DMZ
## -- Connections to ports not handled above will be forwarded to 192.168.2.2
iptables -t nat -A prerouting_wan -j DNAT --to 192.168.2.2
iptables -A forwarding_wan -d 192.168.2.2 -j ACCEPT