Customizing Windows Vista Calendar Display

Question

I want to make a program using Delphi, to watch and wait windows vista calendar displays (the two windows that appear bottom right of the screen when you hold or click the mouse on the time in systray), and when they appeared change their contents to make my own calendar (Persian calendar). Is there any way to change the contents of calendar control (SysMonthCal32) with windows messages?

Sample:

Answer 1

Finally I did it. The program must watch for creation of calendar window and then place its own calendar on it using SetParent API function.
You can see the result app in http://www.dihav.com/pghcal/.