Alright, I got IP-Masq (SNAT) up and running.
Here is how I did it.
1. Get eth0 and eth1 working
2. Compile kernel to support ip-masq (check ip-masq-howto from tldp.org for the configs)
3. Download rc.firewall from
http://www.ecst.csuchico.edu/~dranch...masq/examples/
4. Edit the ip-addresses and remove loading modules if you compile everything into the kernel like I did.
5. Place rc.firewall at /etc/rc.firewall and chmod 700 rc.firewall
6. ./rc.firewall
(I also chmod +x rc.ip_forward; not sure it is needed since rc.firewall will enable ip forward also).
And I am up and away. Tested it, everythign work so far.
But since I used strong firewall script, now I can't ssh or ping my Masq-server from outside. Need to configure the rc.firewall again, later.