Text vars and lockroot

Hi
I have used this simple technique to read a flv’s load process

onEnterFrame = function(){
text_var.load_text = (net_stream.bytesLoaded/ net_stream.bytesTotal)*100;
}

It works fine by itself
as seen in [COLOR=#003366]#[/COLOR]
but not when the swf is loaded onto the index stage.

but here it is if you goto #
and click on the movieclip section.

cheers for any pointer