Comment 37 for bug 554514

I've got the same problem.
1. Right after starting kde
$ akonadictl status
Akonadi Control: stopped
Akonadi Server: stopped
Akonadi Server Search Support: available (backend: Virtuoso)

2. When I start kontact, akonadi displays the error: "No resource agents found". But executing again
$ akonadictl status
Akonadi Control: running
Akonadi Server: running
Akonadi Server Search Support: available (backend: Virtuoso)

3. Now closing kontact and starting it again akonadi is working, without an error.

My next try was just after logging into kde session
1. $ akonadictl start
Now akonadi is running, and kontact is working without errors.

So a possible work around may be to execute akonadictl start as a script in the autostart, right after logging in.