ActionScript 3.0 :: Use SeekToNavCuePoint Outside Of A Component?

I'm trying to add a button which navigates to a cuePoint, but am getting this error:
 
TypeError: Error #1006: seekToNavCuePoint is not a function.
at videocue_fla::MainTimeline/buttonFunction()

I can make this work when using the FLVPlayback component, but when trying the same thing on a NetStream instance it chucks up that error.
 
Is this code no good for NetStream? Or is this not even possible? It doesn't work even after the cuePoint has happened.
 
Testmove.addEventListener(MouseEvent.CLICK, buttonFunction);function buttonFunction(evt:MouseEvent):void {client.seekToNavCuePoint ("Testmove");}