How to execute a function on the root from a movie clip

1

Hello,

I am fairly new to AS3.0, so this is kind of a newbie question.

I have a function on the root timeline called addWave()

I would like to call that function from within a movie clip, but when I use
root.addWave(); or parent.addWave();
Flash acts like I am crazy

1061: Call to a possibly undefined method addWave through a reference with static type flash.display:DisplayObject.

I would like to know how to run a function from another timeline in AS3.0.

PS: I am not using packages, so please give me a packageless solution

Thanks.