how to fight fake email addresss?

[Ugo Bellavance]

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Jason wrote:
> Hi,
>
>    I'm curious to know whether MailScanner will do a DNS lookup to make
> sure the sender's domain matches its ip.

What do you mean exactly?  Check that the domain exists?  That's the
MTA's job.  Check that the smtp server used is the good one?  That is
SPF and there are SPF rules in SpamAssassin.

>
> Jason

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