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 symfony 's PO files:

source does not specify a priority
gettext: src/Symfony/Component/Translation/Tests/Fixtures/empty-translation.po: can't guess language
gettext: src/Symfony/Component/Translation/Tests/Fixtures/empty.po: can't guess language
gettext: src/Symfony/Component/Translation/Tests/Fixtures/escaped-id-plurals.po: can't guess language
gettext: src/Symfony/Component/Translation/Tests/Fixtures/fuzzy-translations.po: can't guess language
gettext: src/Symfony/Component/Translation/Tests/Fixtures/missing-plurals.po: can't guess language
gettext: src/Symfony/Component/Translation/Tests/Fixtures/plurals.po: can't guess language
gettext: src/Symfony/Component/Translation/Tests/Fixtures/resources.po: can't guess language
      

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.