netfilter question

["John Black" <black@arbbs.net>]

I'm trying to install a gateway/router with Red Hat 9 kernel 2.4.24 and the
stock
iptables 1.2.7a, with full NAT compiled into the kernel. I have read the
howto
at netfilter.org, even have the same line of code.  But it sill will not
change
the source address.

here is the line of code and the result of the command <iptables -L -nvx>

iptables -A FORWARD -i eth0 -o eth1 -m state --state ESTABLISHED, RELATED -j
ACCEPT
iptables -A FORWARD -i eth1 -o eth0 -j ACCEPT
iptables -A FORWARD -j LOG

Chain INPUT (policy ACCEPT 127 packets, 9436 bytes)
pkts  bytes target  prot opt in   out   source   destination


Chain FORWARD (policy ACCEPT 36 packets, 1709 bytes)
pkts     bytes target      prot opt    in    out     source
destination
 0       0    ACCEPT   all     --    eth0  eth1   0.0.0.0/0    0.0.0.0/0
state RELATED, ESTABLISHED

 0       0    ACCEPT   all     --    eth1  eth0   0.0.0.0/0    0.0.0.0/0

 0       0    ACCEPT   all     --    *        *      0.0.0.0/0    0.0.0.0/0
LOG flags 0 level 4

Chain OUTPUT (policy ACCEPT 74 packets, 8568 bytes)
pkts  bytes target  prot opt in   out   source   destination


I new to security of a network. Am I close?

thanks
john