RFC 3977, "Network News Transfer Protocol (NNTP)", October 2006Source of RFC: nntpext (app)
Errata ID: 1526
Publication Format(s) : TEXT
Reported By: Julien Élie
Date Reported: 2008-09-24
Rejected by: Lisa Dusseault
Date Rejected: 2009-11-23
Section 9.2 says:
mode-reader-command = "MODE" WS "READER"
It should say:
mode-command = "MODE" WS mode-variant mode-variant = keyword
Even though the ABNF syntax directly treats MODE READER as a command, MODE is
a base command and READER is a variant of this base command.
Therefore, when the keyword is an invalid mode, the 501 response code is sent:
[C] MODE UNKNOWN
[S] 501 Unknown MODE variant
the errata contributor asked me to reject it.