Aborting a selection callback

Hi,
another "best practice" question:
I have a list-panel with objects, selecting a object in the list shows info
about the object in another pane to let the user view/modify the slots of
the object.

If the slots of an object has been edited, I want a yes/no/cancel popup-pane
asking the user if he wants to save the edits. My problem is the cancel
action. When the selection-callback fires, the new selection is already
highlighted, and aborting (canceling) the callback maked the new
selection the selected object in the list.

Is there a way of firing a yes/no/cancel "gatekeeper" before the selection
happens? Or should I "manually" reset the selection to the previous
selection when the user chooses cancel?
-- 
  -asbjxrn