RFC Errata
RFC 4707, "Netnews Administration System (NAS)", October 2006
Source of RFC: INDEPENDENT
Errata ID: 5817
Status: Reported
Type: Technical
Publication Format(s) : TEXT
Reported By: Julien Élie
Date Reported: 2019-08-18
Section 6.3.3.3 says:
date-answer = "511" [answertext] CRLF text CRLF "." CRLF
It should say:
date-answer = "511" [answertext] CRLF [1*text CRLF] "." CRLF
Notes:
I suggest [1*text CRLF] that is to say a possible non-empty line.
We need at least *text anyway (several characters), as shown in the example in Section 6.3.3.3.