updateElement( ) on every change?

Is there a simple configuration change that will make CKEditor (4.1) call updateElement() on *every* change (i.e. each keypress, or content-changing toolbar click, etc)?

Reason: I'm trying to use formSaviour (https://github.com/ianand2/Form-Savior) on a form with a CKEditor instance in it, but as the underlying <textarea>'s value isn't changing, it doesn't think the form data has altered.

If not, then what's the best way to manually write a callback to do this, which can be included in the instantiation code, i.e. CKEDITOR.replace()