ipfilter - port forward question

[Darryl Hoar]

Greetings,
I have a FreeBSD 4.7S that is my firewall it also does nat for my 
internal home LAN.

Firewall is running ipfilter.  I have a full and nice set of rules that
work well.  Occasionally I like to play an online racing game.
Since I have DSL I'd like to host.  I created an open set of rules
for the firewall named /etc/ipf.game.  It contains

pass out from any to any
pass in from any to any.

I use ipf -Fa -f /etc/ipf.game to flush and load the rules.

/etc/ipnat.rules contains

map ep0 192.168.1.0/24 -> 0/32
rdr epo 24.225.33.0/32 port 31240 -> 192.168.1.35 port 31240 tcp

the online game uses port 31240.  My internal machine that I'm
playing on is 192.168.1.35.  It is running Windows XP Pro.

The above doesn't work for the game.  Users can't connect.

What am I screwing up ?

thanks,
Darryl