These two classes here sort of emulate the interface from the Zend Framework API with regard to ZendFeedWriteFeed for constructing an Atom feed. Except we do it in a DAViCal way, and we have some huge limitations:
Located in /inc/AtomFeed.php (line 20)
Documentation generated on Fri, 13 Jan 2012 23:44:52 +1300 by phpDocumentor 1.4.3