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[Alexei]

Hello, freebsd-net.

I'm going to build some mail system, so I need some advice.
There is a network with a 'MS Exchange' as a mail server and
'someintdomain' as an internal mail domain. I also have an internet
domain, for example 'mydomain.com'. There is a freebsd box as a
gateway for my network, and 'MX' record of 'mydomain.com' will point
on it's address.
What I need:

- when someone sends mail from internet to 'vasya at mydomain.com', my gw
replaces vasya at mydomain.com with 'vasya at someintdomain' and sends it to
Exchange server
- when someone from my internal network (vasya at myintdomain) sends mail
to some internet mail address (ie sends it to ms exchange server and
exchange sends it to gw), my gw replaces 'From:' and 'Reply-to:'
fields vasya at someintdomain -> vasya at mydomain.com

Is that real? How can I realise this system? Or, maybe, there is some
other way to get the result I need?

PS: 'Exchange' server has 'grey' address (192.168.0.0/16) and I don't
want allow him connect to the internet directly.
PPS: Sorry, if this question is not suitable for this maillist, so
advise me please where to ask.




-- 
Grats,
 Alexei                          mailto:root at sovetnik.org