Products.CalendarX is an add-on for Plone that displays Events  in monthly, weekly and daily views. There is also localization for various languages included.
The codebase is old (i.e. Archetypes content and RestrictedPython scripts) and does not conform to modern Plone development best practices.
Version 0.9.7 and higher are Plone 4+ compatible. For Plone 3.x, please use an older release.
Other similar add-ons:
Source code and issue tracker:
|||I.e. event-ish content, e.g. events created with the default Plone event content type.|
Products.CalendarX is already very old codebase. It is stable, but does not see frequent updates anymore. For similar addons see