Version: (using Devel) OS: Linux Installed from: Compiled sources The Calendar plasmoid only displays the global locale Calendar System, but this is too restricting for users is countries where multiple calendar systems may be in use and the user may wish to have plasmoids displayed for each. This is a common usage scenario in areas of the Middle East where both the Gregorian and Hebrew or Islamic calendars are used in parallel. This is supported by the kdelibs KDatePicker / KDateTable widgets, see KDateTable::calendar() and KDateTable::setCalendar() for an example of how to do this.
To be clear, it appears that the OP is requesting that _both_ calendars be supported. This is important in areas where daily life goes by the Gregorian calendar but holidays and family events (weddings, birthdays) go by a different calendar. See also related bug for increasing the effectiveness of non-Gregorian calendars in KDE: https://bugs.kde.org/show_bug.cgi?id=149614
Yes, it would be analogous to the Clock plasmoid where you can have multiple clocks displayed with different timezones set in each, so you should be able to have multiple calendars displayed with different calendar systems set in each. It looks like we will soon have more calendar systems available from India and China, so this need will only increase.
Implemented by commit 1035364 for KDE4.4, forgot to BUG: