As of version 8.13, sendmail added an anti-spam feature called "greet_pause". It is both simple and clever.
(...)
I've heard from a few folks that greet_pause can block some legitimate sites. Those sites should probably fix their mailers, but until that happens you can always whitelist them by adding more entries to your access file.
[^] # Re: Precision sur la page d'aide
Posté par Gniarf . En réponse au journal La mort des serveurs mail auto-hébergés. Évalué à 2.
As of version 8.13, sendmail added an anti-spam feature called "greet_pause". It is both simple and clever.
(...)
I've heard from a few folks that greet_pause can block some legitimate sites. Those sites should probably fix their mailers, but until that happens you can always whitelist them by adding more entries to your access file.