On Sun, 22 Sep 2013, John Levine wrote:
Some mailers attempt to clean their address lists by going through the
list and doing EHLO, MAIL FROM, RCPT TO, and dropping the ones where
the RCPT TO fails.
We all know why this is abusive, and why it doesn't work (greylisting,
wildcards, reject after data, etc.) but is that written down anywhere?
If it is, it's not in a place that's easy to find.
But much as I think it is bad practise, do we really all 'know' this, as
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