Thanks for bumping me.
ok so I think this is what you need.
On your Linux box you'll need to have a simple script run to switch on the NAT. "This is not going to firewall off anything but it will help hide your internal addresses"
So create a script in the directory /etc/rc.d called nat.sh.
put this in the script:
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# start Natwall
ipchains -F
# Accept all access.
ipchains -P input ACCEPT
ipchains -P output ACCEPT
ipchains -P forward ACCEPT
# sets timeout values for FIN flags etc..
ipchains -M -S 7200 10 60
# magic NAT setting for MASQing
ipchains -A forward -s 192.168.0.0/24 -j MASQ
# eof
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Now go and install some software called "ipmasqadm" from
ftp://ftp.redhat.com/pub/contrib/lib....4.2-3.src.rpm
Once you have installed this active it in the /etc/rc.d/rc.local file with the following lines at the end of the file.
-----------------------
/etc/rc.d/nat.sh
modprobe ip_masq_portfw
ipmasqadm portfw -a -P udp -L 55.65.228.185 32766 -R 192.168.0.4 32766
# add more lines with all the ports you need until it's correct.
------------------------
now run the rc.local file.
Note: Netfilter has this feature added as standard so if you find you can't get this working, use iptables.
/raz