Failure when accepting an event.

[Pierre-Yves Strub]

Hi,

I'm running the 3.0 branch of the Kolab calendar/libcalendar plugin with 
a DB as backend.

When accepting a mail attached event, I got an internal error triggered 
in the (calendar.php) import_mail_event function, line 1970.

PHP Fatal error:  Call to a member function format() on a non-object in 
/.../calendar.php on line 1970

The "non-object" seems to be $event['changed'] that is set nowhere. I 
suspect that the backend `new_event' should set that field. Currently, 
the function feeds the DB with $this->rc->db->now() for the `changed' 
SQL column, but let the event PHP record untouched.

Likewise, it seems that the function updating the event should update 
the PHP record `changed' field.

Cheers,
-- Pierre-Yves.