FW: Trying to get a Subnet NATted

["Kevin L. Collins" <kcollins@qx.net>]

First I want to appologize if this makes it to the list more than once,
I've been having trouble joinging the list.

I've got a strange situation where I receive data from my WAN links
across the same Interface as my External Interface.

Let me try to explain it with ACSII art....
+--------------+
|     WAN      |
|10.200.9.x/24 |
|10.200.10.x/24|
+------+-------+
       |
      aDSL
       |
+------+------+
|Real Internet|
|   Subnet    |
|   eth0 of   |
|  Linux Box  |
+-------------+

I need to be able to bring the packets from the WAN subnet and then
"SNAT" them to allow them to go back out on to their final Internet
Destination.  As it stands right now, the Linux machine is simply
routing them through to the Default Gateway and my ISP's router is
killing the packets because they are "improper" as they have a
destination address in the Private LAN subnets.

What I would to do is have IPTABLES apply the SNAT arrangement that I
have configured for my Internal LAN.  Is this even possible?  And if so,
how would I go about doing it?  I've tried several things over the past
week tro make it happen, but nothing is working.  I think I have to do
something BEFORE the routing takes place, but I'm not sure what.  ANY
help would be GREATLY appreciated.

Kevin L. Collins, MCSE
Systems Manager
Nesbitt Engineering, Inc.