Garbage collection

Hi, I haven’t managed to find a huge amount of info on the AS3 garbage collector although gskinners blog has some good articles. My question really is this:

Will the garbage collector automatically free resources from an object’s members (assuming I have no references to them elsewhere and have removed all event listeners) once I remove the parent object from the stage and set its reference to null (as Java behaves)?

Or should I explicitly remove the member objects from my parent object and null them also?

ie.

public class A extends Sprite{

     private var bInstance:B;

     public function A() {

         bInstance = new B();
         this.addChild(bInstance);

     }

     //should I implement a function such as this or is it completely unnecessary?

     public function destructor():void {

         this.removeChild(bInstance);
         bInstance = null;

     }
}

Cheers,
Alex