How to disable dates in calendar

Hi, I´ve read the documentation e some forums threads but I didn´t find a solution to my problem. There is a way to disable some dates and hours in Calendar? For example, in 01-05-2012 only 8:00am to 11:00am and 2:00pm to 5:00pm should be avaliable to insert events, all the other times should be disable (with a diferent color and with no pop-up to insert event). Is this possible?

If it´s not, can I at least change the color of some hours or days, for example, 01-05-2012 from 0:00am to 8:00 with a diferent color than the rest of the day? (I´m thinking in day view and week view).

Thanks