not properly display Cyrillic names joomla users

Hi!
I have installed the latest version of DHTMLX Scheduler for Joomla.
But I was faced with incorrect display of the user name in Russian.
Database joomla (2.5) encoded UTF-8.
So is displayed in the admin panel and frontend.
Please help to fix the problem.
Thank

Dear developers,
help fix this problem please!

fix this problem for me

create file /etc/mysql/conf.d/utf8_charset.cnf

[mysqld]
character-set-server=utf8
collation-server=utf8_unicode_ci
skip-character-set-client-handshake

[client]
default-character-set=utf8