There's been a lot of request for web and windows controls supporting multiple cultures and calendars, like the already existing WinForm Controls of Farsi Library. The existing ASP.NET Calendar control does not render correctly when used in other cultures and this is the case when you're using FA-IR culture. Although this problem is partially because FA-IR has a wrong calendar set for its default calendar (GregorianCalendar instead of PersianCalendar this has its own story too), there's no workaround. What I did was to create a new control to correctly render the calendar information in Gregorian Calendar, Persian Calendar and Hijri Calendar.
The control currently works exactly as ASP.NET calendar, meaning it supports all the use cases of standard ASP.NET calendar control like styling, using on update panels, etc. This control with a complementary DatePicker control will be added to the Farsi Library project as I'm planning for the next major release. The pre-beta sources will soon be available in case you are interested.