How to call class method from a movieclip?

Hello!
I am having a big problem, hope someone can help me.

I have made a class which i import in my flash file. The first and only frame of the file looks like this:

import myClassFolder.*;
var myClassInstance:myClass = new myClass(this.stage);
stop();

Inside the class i am attaching a movieClip from a library and declaring a methof:

public class myClass extends Sprite{
var contentMCs:MovieClip = new contentMC();

}
public function myMethod(){
}

The contentMC contains 8 frames, each of the frame has a movieClip.

In the frame 2 of the contentMC MovieClip i want to call myMethod of the myClass.
Anyone who know how to do this?
Thanks in advance