How to call gotoAndPlay function activated in _root from an external MC with AS3?

Dear all,

I am newbie in AS3. I have a problem:

**parent movieclip:
**var ldr:Loader = new Loader();
ldr.mask = rect;
var url:String = “yes/color_match.swf”;
var urlReq:URLRequest = new URLRequest(url);
ldr.load(urlReq);
addChild(ldr);

–> the external MC is color_match.swf
**

Problem is: **how can I call _root to gotoAndPlay(frame) in the child (which is color_match)?
I tried and prompt error: color_match.as, Line 87
**1061: Call to a possibly undefined method gotoAndPlay through a reference with static type flash.display:DisplayObjectContainer.

**Anyone can help me? It takes me quite lots of time for this stupid code.

Thanks,
michoux