Apple today announced the release of iCal 1.0.1, an update to the company's calendar application, and iSync 1.0, the first final release of its synchronization software. Both releases require Mac OS X 10.2.3 and offer performance improvements, bug fixes, and feature tweaks.
http://www.apple.com/pr/library/2003/jan/02ical_isync.html
http://www.apple.com/ical/
http://www.apple.com/isync/