I'm using ZCS 5.0.18 OSS and iCal 3.0.7 (Mac OS X 10.5.7) via CalDAV.
When I create an appointment with attendees from Zimbra Web, the invitation correctly shows my email as the organizer:
However when using iCal, the invitation shows postmaster as the organizer:
The functionality is working as expected (i.e. the organizer does receive the confirmation no matter which email is there), however it's visually wrong.
Is this a known issue? I just started using this feature and I couldn't find any relevant threads using the search.