CalDAV support for KDE Kontact
http://code.google.com/p/kcaldav/

This resource provides CalDAV support for Kontact. It is intended to provide the same level of CalDAV support as other major calendaring clients such as Evolution and Sunbird.

The plugin is developed as a standard KResource on KDE 4.4. Currently, Akonadi has a KResource compatibility layer, so the plugin will operate within that framework.