At 20:23 16-08-2011, Hector Santos wrote:
So the only highly subjective argument which I will never buy as
being absolute in either direction is that the receiver MUST ALWAYS
deliver with the 250 even for invalid messages.
As a clarification, acceptance of a message (SMTP transaction) does
not equate with delivery, i.e. the SMTP server already sent the 250,
it cannot send a 550 as it already provided a reply code. John
commented on the server sending a NDN if it deems fit. Randall
Gellens commented on the timing issue. I haven't seen anyone arguing
in this thread that the receiver must always deliver.