The following issues with 2821bis-01 are still open, and a solution to
them is being postponed to after 2821bis-02 has been posted.
2) Check VRFY/EXPN text in Section 3.5.3
7) Switch conformity language to 2119 form
10) Add discussion of mail rerouting via 251/551 to Security
16) General use of "is permitted", etc
19) Comments on literals in EHLO - remove either "Extended-literal"
or the text in 184.108.40.206 that describes it.
20) RFC3552 and Security Considerations