Animate ellipse

[J_F_S]

How can I animate the object values of a ellipse?
If I create a ellipse I can't change the values of it further.
Have someone a tipp for me how I can solve this?

[kglad]

you create a canvas or as3  project?

you click the oval tool and create an ellipse?

you try to change the width and/or height (in the properties panel) and have a problem?