Comment 5 for bug 963460

It'd be an improvement to use the locale name anyway, though, as part of ubiquity's code to mangle locale names into language pack names includes generally stripping the country part. Compare:

  $ check-language-support -l en_GB --show-installed
  firefox-locale-en gimp-help-en language-pack-en language-pack-gnome-en libreoffice-help-en-gb libreoffice-l10n-en-gb myspell-en-au myspell-en-gb myspell-en-za openoffice.org-hyphenation poppler-data wamerican wbritish
  $ check-language-support -l en --show-installed
  firefox-locale-en gimp-help-en hunspell-en-ca hunspell-en-ca hunspell-en-us hunspell-en-us hyphen-en-us language-pack-en language-pack-gnome-en libreoffice-help-en-gb libreoffice-help-en-us libreoffice-l10n-en-gb libreoffice-l10n-en-za myspell-en-au myspell-en-gb myspell-en-za mythes-en-au mythes-en-us openoffice.org-hyphenation poppler-data wamerican wbritish

I have the fix here now, I think; I'll commit it after some testing.