exim4 problem delivering locally

[Mumia W <mumia.w.18.spam@earthlink.net>]

Hello. I've configured exim 4.72 in Debian Squeeze to send mail externally though a "smarthost," but now local sending of mail doesn't work as I expect.

My machine is host-1.mydomain.local. How do I get exim to send all mail for *.mydomain.local to host-1.mydomain.local?  In other words, I want mail for mumia@mydomain.local to go to mumia@host-1.mydomain.local.

How is this done?

PS.
I'm hoping to be able to do this without setting up a name-server locally, because I've never done that before, and I could mess things up even more.


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