I just installed moodle version Moodle 3.1+ (Build: 20160603)
There is problem with characters öäÖÄ because they will show as öäöä in chat window (in database tables they will appear right and characters are ok in emails.)
I have also moodle version Moodle 3.0.4+ (Build: 20160517) where this works OK.
Any help where to debug this?