communicating between subnets

[Praveen Kallakuri <praveen@neb.rr.com>]

here is the scenario.

subnet 1
192.168.1.x
contains a gateway 192.168.1.1 (with dual network interface) connected to
the internet and a number of clients

subnet 2
192.168.0.x
contains a gateway 192.168.0.1 (with dual network interface) connected to
the internet and a number of clients

a friend and myself were trying to connect these two subnets. 

we got a new machine (a laptop running woody) with dual network
interfaces

eth0: (subnet 1) 192.168.1.125
eth1: (subnet 2) 192.168.0.125

we enabled ip forwarding on the laptop. (set a file
/proc/sys/net/ipv4/ip_forward to 1)

for the purpose of testing, we had two clients, one each on the two
subnets.

test client in subnet 1
route 192.168.0.x requests to 192.168.1.125

test client in subnet 2
route 192.168.1.x requests to 192.168.0.125

having done this, we were still not able to communicate between the
test clients. both test clients can ping their respective interfaces on
the laptop and even the interface in the other subnet. but they cannot
communicate with each other. what are we doing wrong or what more do we
have to do? 

thanks