[plug] iptables rule

[Jon L. Miller]

I have a home network that connects to the office network with the
following configuration

home network 192.168.2.0
office network 192.168.1.0

The way it was setup /etc/ppp/options.ttyS1
192.168.1.3:192.168.1.99 proxyarp

While it can dial in I cannot access the mail server from the
192.168.1.0 network nor can I ping past the 192.168.1.99.

I'm assuming this is a firewall issue and what I need to know is what
rules needs to be applied using iptables.
I thinking I need to accept all usual incoming traffic from the office
network. I also need to have all usual traffic going from the home
network to be accepted.

TIA