Wtf rollovers

can someone explain this:

I have a movieClip on stage, inside is a dynamic textfield, and I have set mc.scaleY = 0;

this is the only code:

mc.scaleY = 0;
mc.buttonMode = true;
mc.mouseChildren = false;

and suddenly everything above and below (on the whole stage) where the movieClip actually is receives mouse, I can see by the button mode.

but it only happens with dynamic text, not static.

I have attached the example: