Has anyone tried to create a drawing widget?

I just tried it out today, but I've found that the coordinates for the cursor dont update very fast so you get the typical jaggy lines draw between points. Anyone figured out a way to do this? Ive tried onMouseMove,  increasing the fps and using onEnterFrame so it samples faster, and also the raw touchscreen corrdinates, none seem to makes a difference.

I'm guessing maybe its just a limitation of the hardware?