Encoding utf8 for the Russian language

I ask you to forgive me for my English

When editing the name of the site in Russian, the name of it is not displayed.
In what may be the problem?
And does the Russian alphabet, when a user logs in.
When editing files .tpl, keeping them in utf8 encoding, all the same Russian letters are displayed signs?????

Help please.
Thank you!

Prescribed in the file config.php this line
@header('CONTENT-TYPE: text/html; charset=utf-8');
Got rid of the problems of coding

but how to do that in the admin сохраняля in Russian?