I have a few huge mailing lists ( yes, they are all legit ) and I need each one to be sent out on their own ip. The box in question has 4 external ip address, and I would like to setup qmail to send any traffic that comes in on one ip out on the same ip. These are all internal ip address and the box is acting as a relay. I need to have the 4 seperate mailing groups all have their own ip of origin.

For instance, if email comes in to 10.0.0.1 it needs to go out 10.0.0.1, .2 out .2, .3 out .3 etc...

Any help is appreciated.

Thanks.