Load text - frame 10

Hi

I got a mc wich contains a stop(1) and a textfield in frame(10) and stop(10).

Outside in the root I got a btn that contains:
loadtext to the text frame and play the mc. --> _root.mc.play()

It dont work !
But if I move the textfield to frame(1) it works - STRANGE!
Why is that? and what do I do?