Have you ever looked at some of the CalDAV Servers out there? I'll save you some time, http://trac.macosforge.org/projects/calendarserver http://rscds.sourceforge.net/ As well as, http://sourceforge.net/projects/modcaldav/ Truthfully, you don't need Cyrus to support a Calendar. Because in all honesty, it's unrelated to mail. If you use Kerberos, LDAP, AD, MySQL for Authentication. Take a look at one of those, tie in that authentication and you're done. Then depending on which one you choose, you can have users share their calendars or not. ... There is enough F/OSS out there to emulate everything you can get with Exchange, and/or any other 'Enterprise' Mail System. No it's not as seamless as Exchange, but it works just fine and it's an open standard. You'll find lots more CalDav Servers, and software in the next 6months to a year. Scott Rudy Gevaert wrote: > If we could ever get a decent calendar system that works together with > Cyrus or other software many people would be happy. > > Rudy > ---- Cyrus Home Page: http://cyrusimap.web.cmu.edu/ Cyrus Wiki/FAQ: http://cyrusimap.web.cmu.edu/twiki List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html