Encoding Cyrillic alphabet

[ngruev]

http://www.pbase.com/ngruev/bulgaria

Hello there,
Look at the comments. Some are in english, some in bulgarian (cyrillic). The ones in cyrillic are unrecognizable. This is a problem that started some months ago. Before that everything was OK.
I've read all about encoding, but nothing has worked. I am using a Windows XP and android browsers. I do not thing this is a problem on my side.
Do you know of this problem? Do you know of any solutions?