Port forwarded packets being dropped - why?

[Guest]

[bitmonkey]

I have set up a port forward as follows:

Protocol: TCP
Incoming IP: <ANY>
Port on incoming: 3333
Destination IP: 192.168.1.2
Destination port: 3333
Enabled: Ticked
Source, IP or network: Left blank

I have applied the rule and it shows up in the list of port forward rules OK, but traffic is still being blocked with firewall log entries like:

     INPUT:DROP     ppp0     KEY_TCP     <SOURCE-IP>  1992    :::::    <MY-EXTERNAL-IP> 3333


Do I need to edit something else? Have I set up the port forward rule incorrectly?

nb. the box 192.168.1.2 (the destination for the port forward) is not on the LAN of endian (which is a DMZ) but behind another firewall attached to that DMZ, all routes are correct, traffic is OK for everything else and the relevant ports are open on the internal firewall (not that that would change anything if endian is dropping the incoming packets before they get to the second firewall anyway) - just thought I'd mention it, but don't think it will be relevant.

thanks

[StephanSch]

You have to forward to the ip of your second firewall and there you have to add another port forwarding rule.