Update squirrelmail to new snapshot, 1.4.23pre14523.
Should be fix PR pkg/50197.

Here is changes from previous pkgsrc's snapshot.

Version 1.4.23 - SVN
--------------------
  ...
  - Added Solarized Light and Solarized Dark themes, by Pavneet Arora.
  - Added associative edit list option widget, with optional folder
    list selector for values
  - Added option to use blank spacer instead of security image ("This
    image has been removed for security reasons.") for replacing
    unsafe images.
  - Full date and time is used as "title" (mouseover) text for dates
    shown on the message list screen
  - Custom Stylesheets are now sorted on the Display Preferences page
  - $xtra in the displayHtmlHeader function is now available in the
    global scope so that plugins can modify it during the generic_header
    hook
  - Added some generic client-side (JavaScript) libraries (including
    an asynchronous server request mechansim). See the new /scripts
    directory (plugin authors can refer to the plugin documentation
    for how to use them)
  - Added optional JavaScript folder list refresh ("check mail")
    mechanisms that try to avoid refreshing if server is not responding -
    see the $check_mail_mechanism setting in config/config.php or the
    "4. General Options ==> "21. Auto check mail mechanism" setting in
    the configuration tool.  (If you do not update your configuration,
    you will get messages in your logs:  "PHP Notice:  Undefined variable:
    check_mail_mechanism in /path/to/squirrelmail/src/left_main.php on
    line 322...")
  - Added advanced control over the SSL context used when connecting
    to the SMTP and IMAP servers over SSL/TLS (thanks to Emmanuel
    Dreyfus).  You can take a look at $imap_stream_options and
    $smtp_stream_options in config_local.example.php in SquirrelMail
    version 1.5.2 for more information.  These configuration settings
    should work the same under 1.4.23:
    http://sourceforge.net/p/squirrelmail/code/HEAD/tree/trunk/squirrelmail/config/config_local.example.php
  - Added ability to show login error from the IMAP server instead of
    traditional "Unknown user or password incorrect" (thanks to Alain
    Williams).  See $display_imap_login_error in the configuration
    file or "4.  General Options ==> 22. Display login error from IMAP"
    in the configuration tool.
  - Configuration tool now shows the SquirrelMail version
  - Added new attachments_top hook to src/read_body.php
  - When resuming a draft, correct (from) identity is now pre-selected
  - Removed overly-restrictive character limitations on address book
    nicknames
  - Prevent session lock-up caused by filters plugin trying to move
    messages in an account that is over quota
  - Added MD5 alternative to directory hash calculation
  - Added ability for administrator to control whether or not users
    can edit their reply-to address ($edit_reply_to in config.php)
  - Added new "login_before_page_header" (boolean) hook; allows
    plugins to have more explicit control over login page header


(taca)