[Exim] Mail gateway with sa-exim and exim

Hi All

We want to install a mail gateway to protect our mail server from spam.
We select exim4 with sa-exim to do this on a separate Debian machine
with a registered IP.

We put our domain name under "relay_to_domains" and modified DNS
entries as follows,

    gateway     MX 10 (this is the newly installed one)
    mailserver     MX 100
    our_isp_server     MX 200

Question is, what is the correct router we have to use? Can some one to
post it please?

Version informations,
    Exim     4.31-2
    SA-Exim 4.0-2
    Debian Sarge

Thanks!

Pradeeper
--

Debian GNU/Linux Sarge (kernel 2.2.20-compact)

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