[flexcoders] Drawing shapes with "holes" and applyng them as mask in AS3

[gabriela.perry]

Hi there.
Im trying to make something that will sound very familiar to
"flashers" around here (sure youre here!)
I need to draw a shape with a hole, and need to apply it as a mask to
an image. Im doing this with Flex. The "hole" in the mask is
dynamically created, thats why Im not using flash to draw a movieclip
as my mask.
Any ideas? Thanx in advance :0)
Gabi