Contextual menus on Mac OS X

I don't seem to be able to get a contextual pop-up menu to work on a  
list-panel. I am trying to use Ctrl-click on Mac OS X to display the  
menu.

This is what I've written:

(defclass mylist (capi:list-panel) ())

(capi:display
  (make-instance
   'capi:interface :title "Contextual Menu Test"
   :layout
   (make-instance
    'capi:row-layout
    :description
    (list
     (make-instance
      'mylist
      :external-min-height 160
      :external-min-width 320
      :items '(a b c))))))

(defmethod pane-popup-menu-items ((f mylist) window)
   (list
    (make-instance 'capi:menu-item :title "Test"
                   :callback #'(lambda (item)
                                 (capi:display-message "Hello ~a"  
item)))))

Any suggestions?

Many thanks,
David Johnson-Davies

+------------------------------------------------------------+
David Johnson-Davies, Human-Computer Interface Ltd
17 Signet Court, Swanns Road, Cambridge, CB5 8LA, England.

Tel: +44 1223 314934, Fax: +44 1223 462562
Email: david@interface.co.uk, Web: http://www.interface.co.uk/
+------------------------------------------------------------+