happens on revision 69.
- edit a versioned file
- commit it with comment 'Bär'
- show log --> 'Bär' is comment
- open context menu on latest item and choose 'Edit comment'
- change comment from 'Bär' to 'Bärchen'
- refresh log
-- > comment changed to 'Bärchen'
This issue has been fixed in revision 71.