Scalable OpenGroupware.org (SOGo) is a project derived from OpenGroupware.Org (OGo) with scalability in mind. The Inverse edition of this project has many feature enhancements: CalDAV and GroupDAV compliance, full handling of vCard as well as vCalendar/iCalendar formats, and support for folder sharing and ACLs. The Web interface has been rewritten in an AJAX fashion to provided a faster UI for the users, consistency in look and feel with the Mozilla applications, and to reduce the load of the transactions on the server.License: GNU General Public License (GPL)Changes:
The ability to define custom recurrence rules from the Web interface. Improvements to the invitation window. A view of the attendees state directly from the calendar view or the event editing window. A message can be composed to multiple recipients from an address book or from the attendees menu of an event. The amount of requests to the database has been slightly reduced with optimisations and the introduction of an object cache.

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