The problem is, when I login through lightdm (pam:lightdm:account), then PAM "User info message", such as "Password expired. Change your password now." is not shown in the system locale, but only is shown in English, that can be a problem for our users. Though on the other hand, when I login through getty (pam:login:account), PAM messages are shown in right locale. I tried to track down the problem, and found in lightdm sources this block of code: http://pastebin.calculate-linux.org/ru/show/11722 As I can see, locale environment variables has passed to PAM after successful authorization, but not before, I do not know whether it is the cause...
Some logs and system info: http://pastebin.calculate-linux.org/ru/show/11717
Conversation in #sssd IRC channel: http://pastebin.calculate-linux.ru/ru/show/11723