Usecase:

john:

• has write priveleges to janes calendar
• has her calendar enabled by default

ida:

• creates a recurring event that have both (john and jane) as attendee
• adds an exception

jane:

• accepts the exception

john:

• decline the exception

jane/john:

• checks her calender to the see the correct status for both

Does not work, because we have no logic to deside what incidence john will update via the itiphandler (kdepimlibs/akonadi/calendar/schadular_p.cpp). The logic so far: only check if, we have write perssisions to the incidence and have the correct exception to touch and it updates only one. So randomly either jane or johns calendar will be updated with the decline of john. And because this is done via status=canceled we will hit T471 as well. Btw. updating janes calendar event with status=canceled would mark jane as declined and not john.