Major Description
... instead of isEnabled() when rendering. This will make it consistent with all other form components, otherwise a call to setEnabled(false) on a form will disable all components except the CheckBoxMultipleChoice which requires special handling at the moment.
FYI, I posted this to the mailing list and there were no objections or reasoning for the current behavior
http://www.mail-archive.com/users@wicket.apache.org/msg46303.html