Re: [exim] Defer as a spam filter

Ron McKeating wrote:

> When an MTA tries to deliver an email, the sender (they were not sure if
> it was the actual sender email address or the sending server helo) is
> looked up in a database, if they are valid senders then the email is
> accepted. If they are not in the database, then the message is given a
> defer, the sender is then written into the database. The idea is when
> they retry they will be in the database as so they accept the email. The
> whole point being that genuine email will retry, spammers do not retry.

This is called "greylisting" and it pretty much sucks. :)

> Now we could implement this with exim, perl and mysql fairly easly. But
> wondered what people thought of it as a policy.

Don't pay them a dime, you can easily DIY. But I wouldn't deploy it
anyway :)

/tom