A Registry for SMTP Enhanced Mail System Status Codes
The specification for enhanced mail system status codes, RFC 3463, establishes a new code model and lists a collection of status codes. While it anticipated that more codes would be added over time, it did not provide an explicit mechanism for registering and tracking those codes. This document specifies an IANA registry for mail system enhanced status codes, and initializes that registry with the codes so far established in published standards-track documents, as well as other codes that have become established in
Normative requirements
This document does not use the RFC 2119 keywords. It states its requirements in ordinary prose, which is why nothing is listed here rather than because nothing was found.