asp:Calendar help required

Hi guys,

 I'm new here, so forgive me for any lack of knowledge. I will also post this in the 'beginners' section of this forum. Basically, I'm making a booking system for a room where I work, using the <asp:Calendar> server control. The control is working well, but I can't find anywhere a guide to help me do what I want to do with it.

 What I want to do is to be able to write stuff into the cells for certain days, so, say I have this room is booked on the 21st of October, I want to write in the cell of the 21st of October, Room Booked. How can I do this using the asp:Calendar control?

 Thanks so much for any responses,

 George.
...