The CalendarParser parser fails on allDay events received from Kerio Server with the following message:
17:21:37,276 ERROR [ajp-bio-8009-exec-74][SyncUtil:596] null
net.fortuna.ical4j.data.ParserException: Error at line 5:Expected [61], read [59]
You may take the following event as an example:
BEGIN:VCALENDAR
BEGIN:VEVENT
DTSTAMP:20150731T163627Z
UID:6d0e86b7-b723-4446-b3e7-59245411b79a
DTSTART;VALUE=DATE;TZID="Amsterdam, Belgrade, Berlin, Brussels, Budapest, Madrid, Paris, Prague, Stockholm":20150801
SUMMARY:Nationalfeiertag
LOCATION:Bern
DTEND;VALUE=DATE;TZID="Amsterdam, Belgrade, Berlin, Brussels, Budapest, Madrid, Paris, Prague, Stockholm":20150802
X-LABEL:0
TRANSP:OPAQUE
X-MICROSOFT-CDO-BUSYSTATUS:BUSY
PRIORITY:5
BEGIN:VALARM
UID:58f9552c-0c48-4048-9581-c133c911bcba
TRIGGER;VALUE=DATE-TIME:19760401T005545Z
ACTION:NONE
END:VALARM
END:VEVENT
END:VCALENDAR
I'm not sure, but maybe the parser is confused by the TZID parameter in DTSTART and DTEND - at least I'am, since I don't understand it's relevance for an all-day event.