Just found it is possible to give a linkage in Flash Professional IDE for symbols that has Sprite class as parent. Previously I was sure the only option is MovieClip.
The question is:
How to make these symbols to play animation at runtime? When I put it on a stage in IDE I can extend parent's timeline and use Loop or Play First propery to control the animation inside of a sprite. But if I instantiate that Sprite derived class at runtime I have no idea hot to animate it :( There are no play() and I don't know how to link it's timeline to parent's one Please help.
Updated: Probably I missunderstand the difference of Shape and Sprite classes. So I am in need for Shape or Sprite instances :)