Changes to the Cyrus IMAP Server since 2.5.3

      * Security fix: handle urlfetch range starting outside message range 
      * Fixed bug: better error messages when reading corrupted twoskip
        databases 
      * Fixed bug: treat autocreate_quota_messages:0 as unlimited 
      * Fixed T203: make autocreate_quota:0 work as documented 

Changes to the Cyrus IMAP Server since 2.5.2

      * Fixed T183: don't crash on login when event notifications are
        enabled 

Changes to the Cyrus IMAP Server since 2.5.1

      * Fixed T179: ptloader should no longer crash in
        ptsmodule_standard_root_dn 
      * Improved consistency of event notification parameters 
      * Fixed bug: no longer run out of memory in mupdate with twoskip
        (mmap leak) 
      * Fixed bug: no longer crash on ctl_mboxlist -d for remote mailboxes 

Changes to the Cyrus IMAP Server since 2.5.0

      * Fixed: allow SYNC_CRC to be optional, making upgrades easier in
        future 
      * Fixed: XFER deletes source mailbox less aggressively, avoiding data
        loss under pathological conditions 
      * Fixed T163: XFER no longer bails out on header CRC mismatch 
      * Fixed T117: now error out silently on non-TLS connections to
        services with implicit TLS 
      * Fixed reconstruct bug: upgrading mailbox format now adds GUIDs to
        shared folders (Thanks Norbert Warmuth) 
      * Fixed T165: xfer no longer fails due to bad version comparison 
      * Fixed xfer bug: version 2.5 is now detected properly 
      * Fixed T109: XLIST behaviour is now compatible with Outlook 2013
        (Thanks Leena Heino) 
      * Fixed T116: LIST now correctly handles domains starting with
        "inbox." 
      * Fixed T120: admin users can now SETANNOTATION correctly 
      * Fixed T118: imapd no longer crashes when selected mailbox is listed 
      * Fixed T156: LMTP no longer incorrectly rejects messages delivered
        using 'deliver' 
      * Fixed T76: lmtpd no longer crashes when delivering to a shared
        mailbox (Thanks Leena Heino) 
      * Fixed quota bug: no longer crash when setting quotas on shared
        folder hierarchies 
      * Fixed compilation problem on Solaris 10 (Thanks Leena Heino) 
      * Fixed bug: QuotaChange event notification now always includes
        maxMessages parameter 
      * Fixed bug: event notifications now include paths for shared folders 
      * Fixed bug: GETMETADATA now handles mailbox patterns correctly 
      * Various fixes to compiling and tool chains 
      * cyradm changes: 

          * createmailbox command now accepts –specialuse flag if server
            supports CREATE-SPECIAL-USE 
          * listmailbox command now returns special-use attribute if server
            supports SPECIAL-USE 
          * listmailbox command now accepts –specialuse flag to list only
            mailboxes with special-use attribute 
          * cyradm now uses LIST and REMOTE rather than RLIST if server
            supports LIST-EXTENDED 
          * mboxconfig now accepts –private flag to switch from default
            shared to private version of an annotation 
          * getmetadata: new command 
          * setmetadata: new command 
          * Cyrus::IMAP::Admin::getinfo now returns a different data
            structure to support the above 
          * Cyrus::IMAP::Admin new ACL flag for modifying annotations 

Changes from 2.4 to 2.5

      * Check the release notes online at
        https://docs.cyrus.foundation/imap/release-notes/2.5.0.html 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta10

      * Properly do time range filtering on a recurring event where the
        recurring component isn't the first component in the iCalendar
        stream. 
      * Properly do time range filtering on an uncompleted task with no due
        time. 
      * Added short-circuits to calculation of recurring event time span. 
      * Faster free/busy calculation for non-recurring events. 
      * Added caldav_mindatetime and caldav_maxdatetime options. 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta9

      * DAV DB changes now occur in the mailbox API which means that
        replication works for calendars and addressbooks. 
      * IMAP XFER is now based on replication. 
      * Added support for free/busy query URL to CalDAV. 
      * Authentication for GET/HEAD requests is now done on-demand so that
        free/busy queries and/or calendar subscriptions can be done
        anonymously (subject to ACL). 
      * Added support for VAVAILABILITY, VPOLL, RSCALE to CalDAV based on
        current drafts (requires libical from git). 
      * Updated http_timezone.c to be compliant with current draft. 
      * Numerous other CalDAV fixes/enhancements. 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta8

      * Fixed bug in parsing of Accept header (now accepts */* and type/*). 
      * Fixed telemetry logging bug (old garbage appearing in log). 
      * Added a workaround for the DELETE bug in MacOS X 10.9.0 Calendar
        client. 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta7

      * Added Timzone Service module along with associated admin tools
        (ctl_zoneinfo, vzic). 
      * Added support for accepting/returning jCal (requires Jansson) and
        xCal data wherever iCalendar data is allowed. 
      * Proxied responses (including chunked) are now piped to client
        rather than being buffered and forwarded. 
      * Better handling of COPY/MOVE between backends (including LOCKs). 
      * Fixed "annotation truncation" bug where the largest allowed
        annotation value was slightly less than 4k (solves problem reading
        CalDavZAP settings). 
      * GET on ./well-known now returns a list of /.well-known/ URLs on the
        server. 
      * Added support for X-HTTP-Method-Override header in POST requests. 
      * Added replacement functions for those not present in libxml2 <
        v2.8.0 
      * Plugged a few more memory leaks found by Valgrind. 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta6

      * Plugged several memory leaks found by Valgrind 
      * Less verbose reconnect communication between frontend and backend 
      * GET on calendar-home-set now returns a list of subscribe-able
        calendars 
      * Auto-provisioning of calendars/addressbooks now works via a
        frontend proxy 
      * Fixed several conformance bugs detected by CalDAVTester 
      * Added support for optionally adding Content-MD5 header to responses
        (see httpcontentmd5 option) 
      * Fixed time-based queries for components other than VEVENT 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta5

      * RSS module now produces Atom 1.0 output rather than RSS 2.0 (we
        prefer IETF standards) 
      * PROPFIND/REPORT allprop/propname requests are now supported 
      * unixhierarchysep is now supported by all HTTP modules 
      * Completely rewrote write_body() - Range requests are now supported
        on non-chunked Content-Encoded data 
      * Added cache control response headers where appropriate to make
        Redbot happy 
      * Fixed handling of telemetry log file descriptors and truncation 
      * Allow GET on calendar collections for "exporting" entire calendar 
      * Fixed POST on calendar collection (add-member) 
      * Fixed parsing of calendar-query filter 
      * Added several CalDAV/iCalendar validation checks based on
        CalDAVTester results 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta4

      * Always verify authorization credentials supplied by the client (a
        proxy may be reusing an existing connection as a different user) 
      * Don't bother supporting Digest qop=auth-int since no clients seem
        to use it 
      * Don't show addressbook mailboxes in IMAP LIST output 
      * Plugged leaked memory found by Valgrind 
      * Better handling of request/response bodies 
      * Added httpprettytelemetry option 
      * Added httpallowcors option (Cross-Origin Resource Sharing) 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta3

      * Plugged leaked memory found by Valgrind 
      * Rewrote list_feeds() to not use memmem() 
      * OPTIONS method can be used without authentication 
      * Better handling of Connection:keep-alive 
      * Added httpallowedurls option 

Changes to the Cyrus IMAP Server since 2.4.17-caldav-beta2

      * Fixed security bug where a user-agent could access files outside of
        httpdocroot. 
      * Changed annotation entry name scheme to be
