Kontact vs. Toltec appointment time glitch

[Albrecht Dreß]

Hi all,

I have a question about the interpretation of the time information in vcalendar appointment invitations.  I created an invitation with Kontact coming with Ubuntu Jaunty (Kontact 1.4.2, Korganiser 4.2.2), containing

<snip>
DTSTART;TZID=Europe/Berlin:20090826T150000
DTEND;TZID=Europe/Berlin:20090826T153000
</snip>

I didn't look into the RFC yet, but at least Horde (coming with kolab 2.2.0) as well as (of course) Kontact interpret this correctly as "1500..1530 local time" (CEST).  However, the Outlook clients (OL 2003 and 2007) using the Toltec connector v. 2.3.1 interpret this as either "1600..1630 local time" *or* as "1700..1730 local time".  Needless to say that this created some confusion...

Can anyone tell me who is to blame for this behaviour - the Kolab server, Kontact, Toltec, or even Outlook?  Any idea how I can fix this?

Thanks in advance,
Albrecht.