The same problem:
============================================================
Setting up bacula-director-mysql (5.0.1-1ubuntu1) ...
debconf: Unknown template field '_description', in stanza #9 of /var/lib/dpkg/info/bacula-director-mysql.templates

dbconfig-common: writing config to /etc/dbconfig-common/bacula-director-mysql.conf
Processing configuration...Ok.
 * Starting Bacula Director...
05-Oct 14:45 bacula-dir: ERROR TERMINATION at lex.c:784
Config error: expected a string, got T_EOL: =
            : line 236, col 12 of file /etc/bacula/bacula-dir.conf
  dbname = ; DB Address = ""; dbuser = ""; dbpassword = ""
                                                                                                      [fail]
dpkg: error processing bacula-director-mysql (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of bacula-server:
 bacula-server depends on bacula-director-mysql (>= 5.0.1-1ubuntu1) | bacula-director; however:
  Package bacula-director-mysql is not configured yet.
  Package bacula-director is not installed.
  Package bacula-director-mysql which provides bacula-director is not configured yet.
dpkg: error processing bacula-server (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of bacula:
 bacula depends on bacula-server; however:
  Package bacula-server is not configured yet.
dpkg: error processing bacula (--configure):
 dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error from a previous failure.
No apport report written because the error message indicates its a followup error from a previous failure.
Errors were encountered while processing:
 bacula-director-mysql
 bacula-server
 bacula
E: Sub-process /usr/bin/dpkg returned an error code (1)
============================================================


And the same during uninstall :
============================================================
2 not fully installed or removed.
After this operation, 0B of additional disk space will be used.
Setting up bacula-director-mysql (5.0.1-1ubuntu1) ...
debconf: Unknown template field '_description', in stanza #9 of /var/lib/dpkg/info/bacula-director-mysql.templates

dbconfig-common: writing config to /etc/dbconfig-common/bacula-director-mysql.conf
Processing configuration...Ok.
 * Starting Bacula Director...                                                                               
05-Oct 14:53 bacula-dir: ERROR TERMINATION at lex.c:784
Config error: expected a string, got T_EOL: =
            : line 236, col 12 of file /etc/bacula/bacula-dir.conf
  dbname = ; DB Address = ""; dbuser = ""; dbpassword = ""
                                                                                                      [fail]
dpkg: error processing bacula-director-mysql (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of bacula-server:
 bacula-server depends on bacula-director-mysql (>= 5.0.1-1ubuntu1) | bacula-director; however:
  Package bacula-director-mysql is not configured yet.
  Package bacula-director is not installed.
  Package bacula-director-mysql which provides bacula-director is not configured yet.
dpkg: error processing bacula-server (--configure):
 dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error from a previous failure.
Errors were encountered while processing:
 bacula-director-mysql
 bacula-server
E: Sub-process /usr/bin/dpkg returned an error code (1)