Unfortunately, I seem to have the same problem, irrespective of the distribution I have in container (debian or ubuntu). The solution that I could find is to firstly generate files for locales in need, for instance:
Code:
locale-gen en_US.UTF-8 ru_RU.UTF-8
and then to set locale variables with:
Code:
update-locale LANG=ru_RU.UTF-8
The reboot of the container is needed for settings to take place.