Scrolling Background ..

Hi ..

I'm trying develop small iphone game with flash cs5, the first step i'm trying to do is scrolling big background with my finger .. the iphone application document size is width 320 x height 480 px, on the stage there is a big image 1280x800 px i want start scroll this big image with touching iphone screen in any direction to make the hidden parts appears .. can someone guide me how start coding this ?