R – Flash AS3 – how to set Imported textfield movieclip as unselectable

I created a graphic in Flash CS4 that contains text. I embedded the appropriate characters then saved it as a MovieClip into my library. I then exported it to an SWC file.

In my AS3 code (using Flex SDK/notepad), I then import the movieclip and assign it some mouse events so I can use it as a button.

Unfortunately, all the text-in-graphics I import this way have the "I" mouse cursor and the text is selectable. This steals the focus from my flash application and is not good!

I know when I have a textfield I can:

var myButton:TextField = new TextField();
myButton.MouseEnabled = false;

But this has no effect when it's a Movieclip I'm importing:

var myButton:MovieClip = new MyImportedButtonGraphic();
myButton.MouseEnabled = false;  // No effect

// Plus some other things I learned:
myButton.selectable = false;    // also no effect
myButton.MouseChildren = false; // No effect

What am I doing wrong?