[Owncloud] calendar sync with lightning -1hour time difference

[Michael Blank]

I have set up synchronization from and to thunderbird/lightning 1.0b7 -
and appointments are synced in both directions.

However, the same events appears in ownclouds web interface always one
hour too early.

I checked the system timezone and time settings on both computers (CET)
(and php also tells me its on CET).

Any idea where I can look for the error? How can I debug the CALDAV sync?

thanks, michael.