I submitted some bugs to the Calendaring tracker
mostly having to do with things messing up when publishing from iCal.
Not sure how much of it is the fault of iCal (in which case we have to
cross our fingers that bug reports submitted to Apple are taken
seriously), or the way Calendaring (and the SchoolTool iCal component)
handles the parsing of these files.

I’m going to check out PloneiCalendar
which also uses the SchoolTool iCal stuff to see if it exhibits the
same problems. That will hopefully help to find out who’s the culprit.