Setting GREETDELAY to "" now has the same effect as not setting it. A 554 response is given if greetdelay shuts down the SMTP session.
* Status messages and error messages now include IP address and process ID.
greetdelay introduces a small delay before an SMTP greeting. It can also optionally enforce RFC 2821's recommendation that SMTP clients not send any commands before receiving the greeting message. With a delay of 30s it has done me a world of good.