[Pkg-roundcube-maintainers] Bug#988264: roundcube-core: Configure script does not set unix socket mysql connection and manually setting it breaks the script

[Kurt Fitzner]

After running dpkg-reconfigure roundcube-core I find that 
/etc/dbconfig-common/roundcube.conf remains unchanged, with the relevant 
bits as follows:

# dbc_dbserver: database host.
#    leave unset to use localhost (or a more efficient local method
#    if it exists).
dbc_dbserver='localhost'

# dbc_dbport: remote database port
#    leave unset to use the default.  only applicable if you are
#    using a remote database.
dbc_dbport='3306'

Procedure:

$ apt-get purge roundcube roundcube-core roundcube-mysql
$ apt-get --purge autoremove
$ apt-get install roundcube
   Installer asks if I want to configure the database with 
dbconfig-common, answer yes
   Installer asks for me to set a password, to which I do
$ dpkg-reconfigure roundcube-core
   Asked for IMAP server (stores answer in config.inc.php)
   Asked for default language, set to en-CA (stores answer in 
config.inc.php)
   Asked if I want to reinstall the database, select YES
   Asked for connection method, select UNIX SOCKET (no apparent effect)
   Asked for authentication plugin, select default
   Asked for database name, select roundcube
   Asked for username, select roundcube
   Asked for password, set it (x 2)
   Asked for configuration account, set to root
   Asked for what http servers to configure, select lighttpd
   Asked if I want to restart lighttpd, select no

Expected behavior: Both debian-db.php and 
/etc/dbconfig-common/roundcube.conf should reflect the selected Unix 
Socket method of connection.

Actual behavior: Both files retain "localhost" as the server and "3306" 
as the port.

I have tried this several times with the same result every time.  I even 
tried using a different password for the roundcube user in the 
reconfigure that I did during the initial install.  The new password 
makes it through to dbconfig-common.  The updated connection method 
setting does not.