There are two problems:
1. Mine
server is not able to manage russian letters
2. Mine
craft has in its font system only this letters:
!"#$%&'()*+,-./
0123456789:;<=>?
@ABCDEFGHIJKLMNO
PQRSTUVWXYZ[\]^_
'abcdefghijklmno
pqrstuvwxyz{|}~‚
... and some special letters (but not russian)
Forget it and use English. I know its bad but if there would be russian letters, there should be Chinese, Japanese, etc. letters, too. And this would be too much
-- thegk01