To use MyCalendar portlet you must add MyCalendar to $HomepageComponents
    in etc/RT_SiteConfig.pm like that :

      Set($HomepageComponents, [qw(QuickCreate Quicksearch MyCalendar
         MyAdminQueues MySupportQueues MyReminders RefreshHomepage)]);

    To enable private searches ICal feeds, you need to give
    CreateSavedSearch and LoadSavedSearch rights to your users.