Use of greek font for lyrics

For some reason I can't enter anything here in the forum with Greek letters, hence I rather write in English than in Greek with latin letters.

I'm using a computer with German Windows 2003 Server. When trying to enter greek lyriks in Musescore, I cannot switch to the Greek keyboard (Just the very same problem as here).

Has this problem occured to anybode else, here? Any ideas for solutions? (could that be due to a Java problem?)

I have posted this same question as an issue, too : #16389: Use of greek font for lyrics

TIA for each and every help!

Aggelos