I'm having a problem with the selected dates automatically changing inside of the calendar just by moving the mouse over the calendar.
To reproduce, put the calendar inside of a busyindicator:
In the code behind, simulate an async call and set IsBusy to true while the call takes place:
Run the code and click on a date in the calendar while moving the mouse in circles over the calendar. After about the third click, the calendar will automatically start selecting dates without having to click the mouse. Its an endless cycle of the busy indicator being toggled on and off and dates on the calendar changing without clicking the mouse.