Loading text in Polish (and other languages with Unicode font) isn't showing properly

Loading text in Polish isn't showing properly - it shows some weird glyphs instead of proper text. (Polish uses unicode font.)

Loading text in English and German shows properly, however.

I belive it might be related to: https://mojang.atlassian.net/browse/MC-32322

Edited to add: As of 13w42b, only Polish letter "ś" isn't showing properly (in "Generowanie świata").