[OT] Can't open .po file in Emacs po-mode

[Csanyi Pal <csanyipal@gmail.com>]

Hi,

My system is Debian GNU/Linux Lenny.

I have installed GNU Emacs 22.2.1 (i486-pc-linux-gnu, GTK+ Version
2.12.11) of 2008-11-09 on raven, modified by Debian, and gettext-el
Version: 0.17-4.

I have edited .emacs file with lines:
(setq auto-mode-alist
  (cons '("\\.po\\'\\|\\.po\\." . po-mode) auto-mode-alist))
  (autoload 'po-mode "po-mode"
   "Major mode for translators to edit PO files" t)

(modify-coding-system-alist 'file "\\.po\\'\\|\\.po\\."
                                 'po-find-file-coding-system)
     (autoload 'po-find-file-coding-system "po-mode")

When I try to open a .po file, I get message:
Loading po-mode...done
insert-file-contents:
Autoloading failed to define
function po-find-file-coding-system

Is this a bug?
How can I solve this problem?

--
Regards, Paul Chany
http://csanyi-pal.info