One of the things we’re excited about for the 0.9 release is the addition of CalDAV scheduling support. CalDAV scheduling is an emerging standard; the first widespread use of it was in Mac OS 10.5, where it allows iCal users not only to store their calendars on a shared server, but also check each other’s free/busy schedules, send each other meeting invitations, respond to meeting invitations, and so forth.
With 0.9, people using Sunbird and Lightning will be able to do all these things, using not only Mac OS 10.5 servers but also a growing number of other CalDAV servers, both open-source and otherwise. And they’ll be able to do so regardless of whether the other calendar users they are interacting with are using Sunbird, Lightning, iCal – or some other CalDAV client we haven’t even heard of yet.
CalDAV scheduling support has just started to appear in nighlies over the last few days. It will be filled out further over the next few, but what it really needs most right now is TESTING! We’re really hoping the community will give this new code a serious workout and help us find whatever bugs remain so that it will be rock-solid for the 0.9 release. As Daniel has noted, testing nightly builds can be dangerous to both your profile and your data – so be careful but please do bang at it and let us know what you find.