Setting the weekday format in Scheduler month view

I am not able to set the weekday format in Scheduler for month view. I am using the control in a very small area, and I need to set the weekday names to be abbreviated (Mon, Tue, Wed, etc.).

I have set the HeaderFormat property on both the GetMonthView() and the scheduler control, and it does not seem to change. I still see the weekday names fully spelled out, and Wednesday will not fit into the allocated area.