MQTT event bus with Unicode strings

I use MQTT eventbus to run openhab1 (win7) as master and rule-less openhab2 (debian) at the same time.

It works nice but the strings are with <?> symbols when there are Cyrillic/Non-latin chars.

With MQTT-spy Java app, I see that openhab1 exports the strings with <?> too. If I publish to the same topic from MQTT-spy I see the Cyrillic properly but on openhab2 it is again with <?>.

Any ideas?