[Exim] exim on firewall

Hello

I to filter mail from spam and viruses on my firewall then forward the clean
mail to the real mailer. ( exchange )

The firewall is Linux and I thought of using exim with exiscan and clamv.

Is this a good solution ?

where I can read about this topic ?

thanks
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Canaan Surfing Ltd.
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Ben-Nes Michael - Manager
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http://www.canaan.net.il
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