anchor.diff:      (send mirror :set-target mirror)
       ;; Also need to specify when an action is sent (i.e. which actions
       ;; result in an action being posted)
  -    (send mirror :send-action-on action-mask)
  +;;;    (send mirror :send-action-on action-mask)
  +    (send mirror :send-action-on #$NSScrollWheelMask)
       ;; We want continuous actions when we can get them...
       (send mirror :set-continuous #$YES)
  -    (send mirror :set-action (ccl::@selector "takeAction:"))
  +    (send mirror :set-action (ccl::@selector "takeScrollerAction:"))
   
       (setf (view-event-mask mirror) +ignores-events+)
       (port-register-mirror (port sheet) sheet mirror)
  
positive.code:   ;; height (or width) of scrollbar        = proportional SIZE of lozenge.
    ;; value                                 = proportional POSITION of lozenge
  
    (let* ((range (- (gadget-max-value gadget) (gadget-min-value gadget)))
  	 (size  (if (eq (gadget-orientation gadget) :vertical)
  		    (bounding-rectangle-height gadget)
  		  (bounding-rectangle-width gadget)))
  
negative.code: 
  ;;; No need to update the scrollbar (most of the time) since Cocoa will move
  ;;; the 'thumb' appropriately. Stick some debug in to see when it's invoked.
  ;;; => As expected, this is invoked all the time.
  
  ;;; I believe it's safe to leave this alone though since the sb will only be
  ;;; redrawn once through the event loop it shouldn't be too inefficient to
  ;;; be changing its value regularly.
  (defmethod (setf gadget-value) :before (value (gadget beagle-scroll-bar-pane)
  					      &key invoke-callback)
    (declare (ignore invoke-callback))
  