Version 1.4.21:
- Build with libgsasl by default again (if found).
- Add IDN support to --configure (build with libidn2 to enable this).

Version 1.4.20:
- No significant changes.

Version 1.4.19:
- Add support for SCRAM-SHA-256-PLUS and SCRAM-SHA-1-PLUS authentication, and
  prefer SCRAM methods over the PLAIN method because of their superior
  properties.

Version 1.4.18:
- No significant changes.

Version 1.4.17:
- Added a new configuration command 'eval' to replace the current configuration
  file line with the output of a command (similar to passwordeval, but more
  general).

Version 1.4.16:
- No significant changes.

Version 1.4.15:
- Added mpopd, a minimal POP3 server that delivers mails from a local mailbox
  in maildir format. It can be used by end users as a way to handle incoming
  mail via mpop with mail clients that insist on using POP3.

Version 1.4.14:
- No significant changes.

Version 1.4.13:
- Added support for SCRAM-SHA-256 authentication via GNU SASL

Version 1.4.12:
- Added support for libtls as an alternative to GnuTLS

Version 1.4.11:
- Added support for XOAUTH2, the predecessor of OAUTHBEARER.
- The passwordeval command can now handle very long input, which can be
  necessary for OAUTHBEARER and XOAUTH2.
- GnuTLS >= 3.4 is required

Version 1.4.10:
- Improved handling of temporary files on Windows systems.
- Re-enabled support for systems lacking vasprintf(), such as IBM i PASE.

Version 1.4.9:
- No significant changes.

Version 1.4.8:
- Added a new socket command and --socket option to connect via local sockets.
- Added a new tls_host_override command and --tls-host-override option to
  override the host name used for TLS verification.
- Fixed the source_ip command for proxies.

Version 1.4.7:
- Minor bug fixes.

Version 1.4.6:
- Minor bug fixes.

Version 1.4.5:
- Fixed OAUTHBEARER.
- Support for TLS client certificates via PKCS11 devices, e.g. smart cards.
- Various small bug fixes and improvements.

Version 1.4.4:
- Added support for the OAUTHBEARER authentication method.
- Several minor bug fixes.

Version 1.4.3:                                                                                                                                                                                
- This version fixes a security problem that affects version 1.4.2 (older
  versions are not affected): when the new default value system for
  tls_trust_file is used, the result of certificate verification was not
  properly checked.

Version 1.4.2:
- To simplify TLS setup, the tls_trust_file command has a new default value
  'system' that selects the system default trust. Now you just need tls=on to
  use TLS; the other TLS options are only required in special cases.
  To make this work without breaking compatibility with older mpop versions,
  tls_fingerprint now overrides tls_trust_file, and tls_certcheck=off overrides
  both (previously, you could not specify contradicting options).
- To simplify setup, a new option '--configure <mailaddress>' was added that
  automatically generates a configuration file for a given mail address.
  However, this only works if the mail domain publishes appropriate SRV records.

Version 1.4.1:
- Fixed our TLS code to support TLS 1.3 with GnuTLS.

Version 1.4.0:
- Using OpenSSL is discouraged and may not be supported in the future. Please
  use GnuTLS instead. The reasons are explained here:
  https://marlam.de/mpop/news/openssl-discouraged/
- As using GNU SASL is most likely unnecessary, it is disabled by default now.
  Since everything uses TLS nowadays and thus can use PLAIN authentication, you
  really only need it for GSSAPI.
- If your system requires a library for IDN support, libidn2 is now used instead
  of the older libidn.
- The APOP and CRAM-MD5 authentication method are marked as obsolete / insecure
  and will not be chosen automatically anymore.
- The passwordeval command does not require the password to be terminated by a
  new line character anymore.
- Builtin default port numbers are now used instead of consulting /etc/services.
- Support for DJGPP and for systems lacking vasprintf(), mkstemp(), or tmpfile()
  is removed.

Version 1.2.8:
- Fix support for ~/.config/mpop/config as configuration file
- Add --source-ip option and source_ip command to bind the outgoing connection
  to a specific source IP address.
- Enable SNI for TLS

Version 1.2.7:
- Add support for ~/.config/mpop/config as configuration file
- Add network timeout handling on Windows
- Fix command line handling of SHA256 TLS fingerprints
- Update german translation

Version 1.2.6:
- Return better error code when one or more accounts fail.

Version 1.2.5:
- Support SHA256 fingerprints for tls_fingerprint, and mark both SHA1 and MD5 as
  deprecated.

Version 1.2.4:
- The system default policy is used with GnuTLS instead of a hardcoded one.

Version 1.2.3:
- A bug in SOCKS support was fixed.
- Handling non-fatal errors in TLS handshakes was fixed.

Version 1.2.2:
- No significant changes.

Version 1.2.1:
- The new configure option --with-tls replaces --with-ssl.
- A new configure option --disable-gai-idn was added.

Version 1.2.0:
- Support for SOCKS proxies was added. This allows mpop to be used with Tor.
- GNOME Keyring support now uses libsecret instead of libgnome-keyring. It is
  now documented how to use secret-tool to manage passwords for mpop; the
  obsolete mpop-gnome-tool script is removed.
- Configuration file security is now only checked if the file actually contains
  secrets such as passwords. (If you still store passwords in the configuration
  file, consider using the passwordeval command or a key ring instead.)
- The GSSAPI authentication method is not chosen automatically anymore, you have
  to request it manually if you really want to use it.
- Libidn is not required for IDN support anymore on systems where getaddrinfo()
  supports the AI_IDN flag and the GnuTLS version is >= 3.4.0.
- SSLv3 is disabled, and the obsolete tls_force_sslv3 command and
  --tls-force-sslv3 option have no effect anymore.

Version 1.0.29:
- No significant changes.

Version 1.0.28:
- No significant changes.

Version 1.0.27:
- No significant changes.

Version 1.0.26:
- No significant changes.

Version 1.0.25:
- DIGEST-MD5 authentication is not considered secure any longer. See RFC 6331.

Version 1.0.24:
- The build system was updated, and as a consequence some options to the
  configure script have changed. See './configure --help'.
- The license of the manual was changed from the GNU FDL to a very simple
  permissive license.
- Unmaintained translations (es, pt_BR) were removed.

Version 1.0.23:
- No significant changes.

Version 1.0.22:
- A new command 'received_header' with a corresponding '--received-header'
  option allows to disable the default Received header if required.
- A new command 'passwordeval' with a corresponding '--passwordeval' option
  allows to set the password to the output of a command.

Version 1.0.21:
- No significant changes.

Version 1.0.20:
- Added support for authentication mechanism SCRAM-SHA-1 via GNU SASL.
- The new command tls_fingerprint allows one to trust one particular TLS
  certificate, in case tls_trust_file cannot be used for some reason.
- The new script mpop-gnome-tool.py manages Gnome Keyring passwords for mpop.

Version 1.0.19:
- When using OpenSSL, mpop now correctly handles NUL characters in the Common
  Name and Subject Alternative Name fields of certificates. This fixes a 
  security problem. Note that mpop is not affected by this problem if GnuTLS is
  used.
- Mpop can now handle mail boxes larger than 2 GiB on 32bit systems. Previously,
  this only worked on 64bit systems.

Version 1.0.18:
- Delivery to MS Exchange pickup directories is now supported, thanks to Julien
  Larigaldie.

Version 1.0.17:
- No significant changes.

Version 1.0.16:
- Mpop now also reads SYSCONFDIR/netrc if the password was not found in
  ~/.netrc.
- Support for the GNOME keyring was added by Satoru SATOH.

Version 1.0.15:
- This version fixes two bad bugs that prevented mpop from correctly retrieving
  mails under certain cicumstances.

Version 1.0.14:
- The configuration command tls_crl_file was added. This allows to use 
  certificate revocation lists (CRLs) during certificate verification.
- The configuration command tls_min_dh_prime_bits was added. This is needed to
  use TLS/SSL with servers that use a small Diffie-Hellman (DH) prime size.
- The configuration command tls_priorities was added. This allows to fine tune 
  TLS/SSL session parameters.

Version 1.0.13: 
- Support for the Mac OS X keychain was added by Jay Soffian.

Version 1.0.12:
- No significant changes.

Version 1.0.11:
- The license was updated to GPLv3 or later (source code) and GFDLv1.2 or later
  (documentation).
- Bug fixes and improvements for large POP3 mail boxes with thousands of mails 
  were made.

Version 1.0.10:
- A bug in the UID handling code was fixed. The bug was introduced in version
  1.0.7. As a consequence, if you update from version 1.0.7-1.0.9, the first 
  invocation of this new mpop version will download all mails from the server, 
  even mails that were retrieved before.

Version 1.0.9: 
- Security fix:
  - APOP authentication is vulnerable to man-in-the-middle attacks. See 
    CVE-2007-1558. Such attacks might lead to password disclosure.
    Therefore, mpop does not use APOP automatically without TLS anymore.
    Additionally, mpop's checks on the APOP challenge were too lax in previous
    versions, making attacks easier than necessary. This has been fixed.
- Security improvements:
  - NTLM authentication is considered insecure because it is undocumented. It 
    is therefore not used automatically without TLS anymore.
  - TLS requires tls_trust_file or a disabled tls_certcheck now, so that it is 
    not silently vulnerable to man-in-the-middle attacks.

Version 1.0.8:
- Improved workarounds for POP3 servers that are not exactly RFC conformant.
  For example, pipelining is now enabled automatically for pop.gmail.com and
  some other servers.

Version 1.0.7:
- Mpop now works with the Comcast.net POP3 server, thanks to a patch by 
  Benji Fisher.

Version 1.0.6:
- The default setting for pipelining is now "auto". "on" and "off" now have a 
  slightly different meaning: they force pipelining on or off regardless of 
  server capabilities.
  If you use pipelining=on and your POP3 sessions hang, switch to 
  pipelining=auto.

Version 1.0.5:
- No significant changes.

Version 1.0.4:
- No significant changes.

Version 1.0.3:
- A spanish translation was added by Carlos Martín Nieto. Thanks a lot!
- GNU SASL support works again (it was broken in 1.0.2).

Version 1.0.2:
- The configuration command tls_force_sslv3 was added. This is needed to use
  TLS/SSL with some old and broken servers.

Version 1.0.1:
- The default UIDLS file changed from "~/.mpop_uidls" to 
  "~/.mpop_uidls/%U_at_%H".
  %U and %H will be replaced with the user and host name of an account.
  This means that every account uses its own UIDLS file now.

  !!! IMPORTANT !!!

  If you update from mpop-1.0.0, you *must* do one of the following:
  - If your ~/.mpop_uidls file contains no UIDs, delete it.
  - If you want to keep using it, add the following line to the "defaults"
    section of your configuration file:
    uidls_file ~/.mpop_uidls

Version 1.0.0:
- Added the option --all-accounts (-a) to query all accounts in the 
  configuration file. Changed the short option for --auth-only from -a to -A.

Version 0.8.5:
- Removed the simple_mbox delivery method because it is unnecessary. Please use
  the mbox method instead.
- Optional support for Internationalized Domain Names (IDN) was added.
  GNU Libidn is required for this.
- mpop will now respond to CTRL+C immediately, because all network operations
  are now interruptible. 
- The options of the configure script have changed! Please read the file INSTALL
  for more information.
- Some minor bugfixes and improvements were made.

Version 0.8.4:
- The only_new command and --only-new option were re-added, but with a slightly
  different meaning. The default behaviour is compatible to previous 0.8.x 
  versions.

Version 0.8.3:
- UIDLS files created by versions prior to 0.5.0 are not accepted anymore.

Version 0.8.2:
- Removed the OpenSSL exception note from the license information.

Version 0.8.1:
- Bugfix: Don't leave stale messages on the server.

Version 0.8.0:
- Fixed handling of servers that do not support pipelining.
- mpop will now always remember mails that were already retrieved and delivered,
  even in case of errors or program termination. These mails will never be 
  retrieved a second time. The only_new command and only-new option were 
  therefore removed.
- The 'connect_timeout' setting was replaced by a 'timeout' setting that applies
  to all network operations.

Version 0.7.0:
- Native language support (NLS) was added. Currently the only supported language
  besides english is german, but it is easy to add more translations (hint, 
  hint)!
- When delivering mail, mpop adds a Received header now
- The parameters pipeline_min and pipeline_max are no longer configurable; they
  are compile time constants now.
- Minor improvements all over the place

Version 0.6.3:
- No new festures, just bugfixes.

Version 0.6.2:
- Delivery to maildir folder is now possible. Example:
  delivery maildir ~/Mail/incoming
- Filter scripts can now use the envelope from address and the size of a mail.
  Example:
  filter ~/bin/my-pop3-filter.sh --from=%F --size=%S  

Version 0.6.1:
- This is a hotfix release because of the following error:
  If TLS is not used and a mail with a line longer than 1023 characters is read,
  a null character was wrongly inserted into that line.

Version 0.6.0:
- Implemented delivery to mbox mailboxes. There are now two methods to deliver
  mails: mda and mbox. You can choose one with the new "delivery" command.
  BEWARE: When switching from 0.5.0, you need to convert your configuration
          file to use the new command by inserting "delivery" before all "mda"
	  commands.

Version 0.5.0:
- Speed improvements through network efficient POP3 command usage and faster 
  UID comparison. Use the pipelining command to speed up your POP3 sessions.
- Added support for the .netrc file: If a password is needed but none is given,
  mpop will try to find it in ~/.netrc, and if that fails, mpop will prompt you 
  for it.
- Nicer output

Version 0.4.3:
- One important bugfix (potential segfault)

Version 0.4.2:
- mpop can now keep track of already retrieved mails. Use only_new=on (or
  --only-new=on on the command line) to process only new messages and ignore
  already retrieved messages. 
  The file to store the lists of unique IDs of already retrieved messages in is
  ~/.mpop_uidls by default. This can be changed with uidls_file/--uidls-file.

Version 0.4.1:
- Added the new connect_timeout command and --connect-timeout option.
- Added specialisation to account definitions. See documentation of the
  account command and the example files.

Version 0.4.0:
- The default_mda command is obsolete: there's a new defaults command to set
  default values for all following commands.
- The password will be prompted for if non is given in the configuration file
- The user configuration file is required to have no more permissions than
  0600 (user read/write).
- Added support for AUTH EXTERNAL
- Various cleanups
- You need GnuTLS >= 1.2.0 now if you want GnuTLS support.

Version 0.3.1:
- --serverinfo is now usable without valid authentication data

Version 0.3.0:
- You can now filter your mails before downloading them by inspecting only the
  mail headers: use the new filter command or --filter option. Your POP3 server
  must support the POP3 TOP command for this to work.
- Added --mda option
- Various bugfixes and cleanups

Version 0.2.0:
- Update to the latest msmtp code base:
  - New command line options; see the man page or the --help text
  - Optional GNU SASL support. In addition to the built-in USER/PASS and APOP
    methods, there's support for PLAIN, CRAM-MD5, DIGEST-MD5, GSSAPI, LOGIN,
    and NTLM. Beware: This has not been tested yet!
  - TLS certificate information output with --serverinfo and -debug
  - Long option support on all platforms (thanks to gnulib)
  - Enhanced almost all commands to allow unsetting of features
  - Changed commands: "tls_nostarttls" is replaced by "tls_starttls off" and 
    "tls_nocertcheck" by "tls_certcheck off"

Version 0.1.4:
- IPv6 support on Windows systems
- *Lots* of small bug fixes and improvements

Version 0.1.3:
- When an error occurs, the so far successfully delivered mails will not be
  undeleted on the server anymore. This should prevent double download of 
  mails.
  
Version 0.1.2:
- This version can be compiled without TLS/SSL support; use 
  --disable-ssl if you really want that.

Version 0.1.1:
- New commands: default_mda, killsize, skipsize
- Important bug fixes

Version 0.1.0:
- initial public release; 90% of the code comes from msmtp
  read the TODO file to find out about missing and untested features!