You can check if a PO file is valid with the following command:

        msgfmt -c -o /dev/null <po file>
      

The following errors were found in bacula 's PO files:

gettext: po/de.po:297:70: invalid multibyte sequence
po/de.po:299:5: invalid multibyte sequence
po/de.po:1767:25: invalid multibyte sequence
msgfmt: found 3 fatal errors
      

Please ask the translator (identified by the Last-Translator field in the PO file), the language team (identified by the Language-Team field) or debian-i18n for a fix.

You debconf templates are translated in only 2 languages. You should send a call for translations.

You can send a call for translation using the podebconf-report-po command (package po-debconf):

        cd <po directory>
        podebconf-report-po --call