[Sqlgrey-users] verify(8) (and similar) with greylisting?

[/dev/rob0 <ro...@gm...>]

Airmail.net is one of those stupid ISP's which uses a callback like
Postfix's verify(8) on all sender addresses ...

Jun 27 18:59:57 sorry postfix/smtpd[5081]: connect from mx1.airmail.net[209.196.77.98]
Jun 27 18:59:57 sorry sqlgrey: grey: new: 209.196.77(209.196.77.98), -undef-@-undef- -> us...@ex...
Jun 27 18:59:58 sorry postfix/smtpd[5081]: NOQUEUE: reject: RCPT from mx1.airmail.net[209.196.77.98]: 450 <us...@ex...>: Recipient address rejected: Greylisted for 5 minutes; from=<> to=<us...@ex...> proto=SMTP helo=<mx1.airmail.net>
Jun 27 18:59:58 sorry postfix/smtpd[5081]: disconnect from mx1.airmail.net[209.196.77.98]

Does this need to be whitelisted? The smtp client did manage to have
the triggering mail accepted:

Jun 27 18:59:58 sorry postfix/smtp[5085]: 9417B4924: to=<us...@ph...>, relay=mx1.airmail.net[209.196.77.98], delay=7, status=sent (250 OK id=1Dmypq-000Mqe-Fe)

I'm not sure it will try again. Won't that mean it will be flagged as
spam?
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