Moving a MovieClip along a Motion Path in AS3

I need to have a MovieClip/Sprite move along a path (which will likely be a Shape object) which is drawn dynamically and is going to be segments of straight-lines that bounces off the walls/edges of the stage.

I now that Flash CS4 itself allows tween animation along a path, but I haven’t been able to find an example of doing similar things in code. Most of the examples I see just deal with the x/y values directly. Is there no way to animate a MovieClip along an existing path object?