COM_MATUKIO_BOOKING_ANNULATION_SUCESSFULL is not translated.
Problem: In
components/com_matukio/controllers/bookevent.php
line 326 should be: $msg = JText::_('COM_MATUKIO_BOOKING_ANNULATION_SUCESSFULL');
instead of $msg = "COM_MATUKIO_BOOKING_ANNULATION_SUCESSFULL";
Regards
Patrik