Dynamically attach a mc but it won't gotoAndPlay?

how come the following attaches but yet won’t gotoAndPlay?

holder = this.attachMovie(“facing-effect”, “facefx”+0, 0);
facefx0.gotoAndPlay(“running”);
stop();

i’ve got that inside of a MC on the stage called FACING(this).

in facing-effect, i got a stop in the first frame, and the second frame is my tween with a label titled “running”.

any ideas?