Things to add to the release notes for the next full release:

------------
NEW FEATURES
------------

- All nmh programs will now warn about multiple profile entries for
  the same non-null, non-comment component.  In previous versions, all
  but the first were silently ignored.
- mhmail now supports all post(8) options, or optionally can use
  send(1) with all of its options.  Its formerly undocumented -resent
  switch has been documented.  And it has new -attach, -headerfield,
  and -send/-nosend switches.
- Default to flock() locking on OpenBSD and Darwin.
- Added -directives support to mhbuild(1) to control whether or not
  mhbuild will honor MIME directives by default.  And added support
  for special #on/#off/#pop directives to control the MIME directive
  processing state.
- Added -messageid switch to send(1) and post(8).  This allows
  selection of the style to use for generated Message-ID and
  Content-ID header fields.  The default localname style is
  pid.time@localname, where time is in seconds, and matches previous
  behavior.  The random style replaces the localname with some
  (pseudo)random bytes and uses microsecond-resolution time.
- Added -clobber switch to mhstore(1) to control overwriting of
  existing files.

----------------------------
OBSOLETE/DEPRECATED FEATURES
----------------------------

- Changed exit status of each nmh command's -version and -help
  switches from 1 to 0.
- The following environment variables were deprecated in nmh 1.5
  and removed from this release:
    MHPOPDEBUG (use -snoop command line switch instead)
    MM_NOASK (use -nolist and -nopause command line switches instead)
    NOMHNPROC (use -nocheckmime command line switch instead)
    FACEPROC (undocumented faceproc feature removed)
- Changed repl and dist default to -noatfile.  The default of -atfile
  was deprecated in nmh 1.5.  If there are no requests to maintain
  -atfile, it will be removed in the future.
- The undocumented -queue switch to mhmail has been removed.
- The undocumented -queue switch to post is deprecated/obsolete
  and will be removed in the next release.  It supports the
  SMTP XQUE verb, which is obsolete according to
  http://smtpfilter.sourceforge.net/esmtp.html
- conflict(8) is deprecated and will be removed from the next release.
- mhtest(8) is deprecated and will be removed from the next release.
- spost(8) has been merged into post(8).  Its functionality is enabled
  by selecting the sendmail/pipe mail transport method, described in
  the mh-tailor(5) man page.  The spost -noalias, -backup/-nobackup,
  -push/-nopush, and -remove/-noremove switches are not supported by
  post.  Note that spost did not support -whom or Dcc, and neither
  does post when using sendmail/pipe.  For backward compatibility,
  spost has been replaced by a simple shell script that exec's
  post -mts sendmail/pipe.

---------
BUG FIXES
---------

- Replaced utilities that operate on pbm files with those that operate
  on pnm files in etc/mhn.defaults [Bug #15152].
- Removed obsolete BUGS section at end of rcvstore(1) man page [Bug #4361].
- Fixed -nocc me doesn't account for Alternate-Mailboxes [Bug #36635].
- Propagate Mail-Followup-To [Bug #5571].