Shorewall users - Feb 2003 - local remote netwoks can not access internet

Hi:

I have three networks:

    A- 192.168.1.0/24  (local)
and
    B- 192.168.2.0/24
    C- 192.168.3.0/24  (remote networks)

My firewall running in A has two nics:

    eth0  64.80.101.nn        public fixed ip connects to the Internet and 
    eth1 192.168.1.9           internal firewall ip connects to local network A

Remote networks B and C connects to network A through router R1 which has IP
192.168.1.254 and outgoing internet traffic is routed through the firewall
192.168.1.9.

In the firewall I configured file zones:

net    internet
A      Zone A
B      Zone B
C      Zone C        

In the interfaces file:

net    eth0    64.80.101.167
-        eth1   detect

In the hosts file:

A    eth1:192.168.1.0/24
B    eth1:192.168.2.0/24
C    eth1:192.168.3.0/24

In the masq file:

eth0    192.168.1.0/24    64.80.101.nnn
eth0    192.168.2.0/24    64.80.101.nnn
eth0    192.168.3.0/24    64.80.101.nnn

In the policy file:

A    net     ACCEPT
B    net     ACCEPT
C    net     ACCEPT
net  all      DROP
all    all     DROP
fw    net    ACCEPT

In the rules file I don''t have any restriction on outgoing traffic from
A,B or C to the Internet.

The problem I''m having is that I do not have access to the internet
from remote networks B and C. However I have access to network A, even I can
ping from B and C to ip 192.168.1.9 (firewall). Network A has access to the
Internet.

How can I know if the problem is the firewall or the router R1.

I''ll appreciate any suggestion.  

--
Juan A Seuc