For those of you, like me, who really hate downloading a
source distribution to see what changed, heres what is
in 2.3.10's doc/changes.html
* Added support for "delayed" delete, in which mailboxes are renamed
to a special admin-only "deleted" hierarchy at the time of the
DELETE (hiding them from the client), rather than immediately
removing them from the filesystem. This allows messages/mailboxes
to be recovered by the admin in case of user error. The mailboxes
and messages can be removed at a later time by cyr_expire. The new
delete_mode and deletedprefix options in imapd.conf controls
whether deletes are "immediate" or "delayed" and the mailbox
hierarchy for "delayed" deletes. -- courtesy of David Carter and
FastMail.fm.
* Fixed the special case of RENAMEing an Inbox, so that it doesn't
keep the same mailbox uniqueid, thus allowing it to replicate
properly (seen state is still preserved).
* Disabled Nagle's algorithm in sync_client and sync_server to
increase the throughput of the replication protocol. -- courtesy
of Wes Craig.
* Added support for a shared \Seen flag on messages (must be enabled
on a per-mailbox basis with the /vendor/cmu/cyrus-imapd/sharedseen
mailbox annotation.
* Added -u and -U options to reconstruct -- courtesy of David
Carter.
* Added SETUIDVALIDITY command to the replication protocol --
courtesy of David Carter.
* Finally fixed (again?) alignment issues on 64-bit SPARC.
* Changed message GUIDs used by replication to be the SHA1 hash of
the messages -- based on work of David Carter and Fastmail.fm.
* Improve the performance of commands that operate on sequence-sets.
The sequence-set is now parsed only once, and the commands operate
on a sorted list of seq-ranges.
* Added new cyr_synclog utility for adding events to the replication
log -- courtesy of Fastmail.fm.
* Added support for PCRE library -- courtesy of Fastmail.fm.
* Added support for disabling duplicate delivery suppression on a
per-folder basis with the /vendor/cmu/cyrus-imapd/duplicatedeliver
mailbox annotation -- courtesy of Fastmail.fm.
* Fixed miscellaneous bugs and build issues.
