You can create secondary calendars within any account and then share them to others, so this wouldn't be a problem other than any limitations of Lightning (and it does have some limitations last I checked; mainly I recall it doesn't handle offline mode very well).
Reminders also work, although I personally use iCal and the Zimbra web client, not Lightning.
If you're not going to use Zimbra's mail (or other non-Calendar features), though, you might look elsewhere such as Apple's (free) Darwin calendar server or DAViCAL. But Zimbra's mail is very nice and you might find it worth switching from your current IMAP server. |