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 hebcal 's PO files:

gettext: po/ashkenazi.po: can't guess language
gettext: po/ashkenazi_litvish.po: can't guess language
gettext: po/ashkenazi_poylish.po: can't guess language
gettext: po/ashkenazi_romanian.po: can't guess language
gettext: po/ashkenazi_standard.po: can't guess language
gettext: po/he.po: warning: Charset missing in header.
                                                                 Message conversion to user's charset will not work.
po/he.po:809: duplicate message definition...
po/he.po:7: ...this is the location of the first definition
msgfmt: found 1 fatal error
      

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.