[Definition]

# Block clients which cannot pass Postfix postscreen pregreet test.
# FYI: http://www.postfix.org/POSTSCREEN_README.html#pregreet
#
# The SMTP protocol is a classic example of a protocol where the server speaks
# before the client. postscreen(8) detects zombies that are in a hurry and that
# speak before their turn.
failregex = postscreen\[\d+\]: PREGREET .* from \[<HOST>\]:\d+:

# while setting up new account, Thunderbird doesn't wait for server connection
# greeting/banner, this causes Thunderbird cannot pass the Postfix pregreet
# test and caught by `failregex` rules listed above (the rule contains
# 'PREGREET' line).
# FYI: https://bugzilla.mozilla.org/show_bug.cgi?id=538809#c41
ignoreregex = postscreen\[\d+\]: PREGREET .* from \[<HOST>\]:\d+: (EHLO|HELO) we-guess.mozilla.org