Sorry for bumping,
I?m not using the text box plugin.
I made my own. I will try to make On "backspace" event and tell you if it works.
"At worst, add a keyboard object and add a blank "On 'backspace' key pressed" event.
It should catch the key and cancel the normal usage of the key."
-Does not work for me
<img src="http://s7.directupload.net/images/130117/a5227jzh.png" border="0" />
Edit3: Added a simple console.log to the action and it works