[O] org-contacts: error on message startup

[Sven Bretfeld]

Hi all

Just trying to use org-contacts. There is an error for me whenever I
start a new message:

Debugger entered--Lisp error: (void-variable completion-at-point-functions)
  add-to-list(completion-at-point-functions 
org-contacts-message-complete-function)
  (lambda nil (add-to-list (quote completion-at-point-functions) (quote 
org-contacts-message-complete-function)))()
  run-hooks(text-mode-hook message-mode-hook)
  apply(run-hooks (text-mode-hook message-mode-hook))
  run-mode-hooks(message-mode-hook)
  message-mode()
  message-pop-to-buffer("*mail*" nil)
  message-mail()
  gnus-group-mail(nil)
  call-interactively(gnus-group-mail nil nil)

Have I missed a point in the setup? I just added (require 'org-contacts)
and threw out all bbdb related code from .emacs and .gnus.el. Is there
anything else to do?

I'm using the latest git version of orgmode (release 7.5.299.gb638),
Emacs 23.1.50.1 (Ubuntu) and Gnus v5.13.

Thanks for help,

Sven