Managing notifications: isModified when back button is pressed

I'm trying to find out if there is any parameter passed to my onSimpleEditorBackClick function that could help us determine if the user has made modifications to his remix.

The Wiki says there should be a isModified parameter but everytime I try to display it I get a '0' whatever has been done in the editor.

Am I missing something or is it not implemented yet ?

Thanks,
David