[New Exporter] deriving from derived backends?

[Rick Frankel <rick@rickster.com>]

Nicolas-

I am trying to derive a backend from another derived backend (i want
to override certain entries in the options-alist), but it does not
seem to work. The menu entries are created, but the in the
second-level derived backend are not being picked up.

Should this work? Or do i need a different approach?

here's abbreviated code:

(org-export-define-derived-backend s5 html
  :menu-entry
  (?s "Export to S5 HTML Presentation"
      ((?H "To temporary buffer" org-s5-export-as-html)
       (?h "To file" org-s5-export-to-html)
       (?o "To file and open"
	   (lambda (a s v b)
	     (if a (org-s5-export-to-html t s v b)
	       (org-open-file (org-s5-export-to-html nil s v b)))))))
  :options-alist
  [...]


;; this is the full exporter definition
(org-export-define-derived-backend s5-xoxo s5
  :menu-entry
  (?s "Export to S5 HTML Presentation"
      ((?X "To temporary buffer (XOXO)" org-s5-export-as-html)
       (?x "To file (XOXO)" org-s5-export-to-html)
       (?O "To file and open (XOXO)"
	   (lambda (a s v b)
	     (if a (org-s5-export-to-html t s v b)
	       (org-open-file (org-s5-export-to-html nil s v b)))))))
  :options-alist
  ((:html-container nil nil "li") ;; this is defined in the html backend
  ;; this is new to this backend
   (:s5-xoxo-root "S5_XOXO_ROOT" nil org-s5-xoxo-root-element)))

If i use e.g., s-X or s-x in the exporter menu,
in exporter functions, :html-container == "div" (which is set in the
html exporter), and :s5-xoxo-root is nil.

tia,
rick