ActionScript 3.0 :: Unable To Use The TextEvent.LINK?

I have a symbol on the stage and under a mask at design time. During the course of events, I add another movieclip to the masked clip already on the stage.This newly-added clip contains yet another clip which contains, among other things, my textfield.So the hierarchy looks like this:

Stage > Masked clip > Clip > Clip with textfield

That textfield's (named 'tf') htmlText property has a standard link, something like <a href="event:http://www.url.com">Click here</a>

After assigning the htmlText, I add the event listener:

Code:
tf.addEventListener(TextEvent.LINK, onTextEvent);
function onTextEvent (evt:TextEvent):void
{ trace (evt.text);}

However, the link itself doesn't even switch to a hand cursor when the mouse is over it, so forget even hoping the even listener will fire!

If I add the clip directly to the stage, it "works," but adding it there isn't an option. As far as I know, I've ensured that all clips along the way have mouseChildren set to true: I just can't think of why it wouldn't be working as-is. I created a simple test in a new file, and that appeared to work..