Want a clock like rotating mask

I’m trying to build a preloader that will give the appearance of a circle filling clockwise like a clock (as the movie loads) - as if the second hand was revealing the circle beneath as it passes by. Can anyone point me in the right direction for a smooth way to do this?

I’m not asking how to build a preloader. I’m asking how to create that appearence described above.

Well, I did it by dividing the circle into section, masking each section on a separate layer. It just seems like there should be an easier way.

http://www.macromedia.com/devnet/mx/flash/articles/adv_draw_methods.html

Draw wedge - very cool. Thanks.