Comment 6 for bug 71386

Thank you for taking the time to report this issue and help to improve Ubuntu.

The sort order you're seeing is in fact correct according to the locale that you're using. Sort, or collation, order is defined on a per-locale basis, because languages don't all have the same alphabetization rules, and for most locales the practice is to ignore "unknown" characters when sorting. This behavior, while debatable, is not something that is ever likely to change, because doing so will break existing software that expects the current behavior from these locales.

You are correct both that setting LC_ALL=POSIX will fix the sorting problem, and that it will break display of the output. The solution to this is to instead set LC_COLLATE=C (or LC_COLLATE=POSIX, if you prefer), which will let you change the sorting order independently of the character set, output language, and other features of the locale.