Syncevolution 1.3 supports owncloud 5. Working are calender, contacts, tasks and notes.

notes are handled as journal for a specific calendar.

It is also possible to have multiple calendars and tasks (one for each calendar) .

Calendars:
backend = CalDAV
database = {link to owncloud}/remote.php/caldav/calendars/{user_name}/{calendar_name}

Adressbook:
backend = CardDAV
database = {link to owncloud}/remote.php/carddav/addressbooks/{user_name}/contacts

Tasks:
backend = CalDAVTodo
database = same as for calendar

Notes:
backend = CalDAVJournal
database = same as for calendar