question about setting routing

[Dariusz Zmokly]

Hi,

I've just bought Pentagram's Cerberus router. It contains BusyBox
v0.61 pre (2005-09-23).
It has 4 ethernet ports. To the first port I've plugged network cable
from my wireless internet modem. So I have three ports left.

When I plug a cable from my computer into second port I can use
internet. BusyBox acts just as a bridge. So I get an IP address via
DHCP request from wireless modem.

What I'm trying to do is to configure BusyBox as a firewall with NAT.
However I've problems with it ;) | logged into a BusyBox and issued
command 'udhcpc' and it worked. BusyBox got an IP address from modem.
But for some reason it can't ping wireless modem (this modem is
pingable from my computer when I run 'iptables /renew' on it).
Obviously DNS resolving doesn't work as well. So there is some problem
with routing but I have no idea where.

Could you give me some suggestions?

Regards,
jacubo