[spinchange]

As micampe points out in this thread, Google is shutting down their CalDAV API [0] in favor of their own proprietary one [1] OwnCloud supports the open WebDAV/CalDAV standard, as do several other self-hosted implementations [2].

[0]https://developers.google.com/google-apps/calendar/caldav

[1]https://developers.google.com/google-apps/calendar/

[2]http://caldav.calconnect.org/implementations/servers.html