Ipython and Aquamacs

I can't get ipython to work with python-mode.el in Aquamacs OS X Tiger. I have
been able to run it successfully on the X version of emacs that I built
separately. Similarly, it works on a Linux distribution that we have.

The problem occurs with the line indicated below (in .emacs startup file):

(setq load-path (append load-path '("<SOME_PATH>")))
(require 'ipython)   <---- Problem occurs here

The following error is generated:

Debugger entered--Lisp error: (void-variable py-shell-map)
  (define-key py-shell-map (kbd "RET") (quote ipython-send-and-indent))
  eval-buffer(#<buffer  *load*> nil "/Library/Application 
Support/Emacs/site-lisp/ipython.el" nil t)  ; Reading at buffer 
position
20680
  load-with-code-conversion("/Library/Application
Support/Emacs/site-lisp/ipython.el" "/Library/Application
Support/Emacs/site-lisp/ipython.el" nil t)
  require(ipython)
  eval((require (quote ipython)))
  eval-expression((require (quote ipython)) nil)
  call-interactively(eval-expression)
  execute-extended-command(nil)
  call-interactively(execute-extended-command)


I placed python-mode.el and ipython.el in
/Library/Application Support/Emacs/site-lisp
as per the ipython instructions for going to python-mode.el. My 
.emacs file has:

(setq auto-mode-alist (cons '("\\.py$" . python-mode) auto-mode-alist))
(setq interpreter-mode-alist (cons '("python" . python-mode)
interpreter-mode-alist))
(autoload 'python-mode "python-mode" "Python editing mode." t)

(require 'ipython)                        ; I added this
(setq py-python-command-args '("-pylab")) ; I added this

as per same instructions (except for the last two lines). Has anyone else
been able to get ipython to work with Aquamacs?

Thanks!

-Tony

--
Tony Mannucci
Supervisor, Ionospheric and Atmospheric Remote Sensing Group
 Mail-Stop 138-308,                     Tel > (818) 354-1699
 Jet Propulsion Laboratory,              Fax > (818) 393-5115
 California Institute of Technology,     Email > Tony.Mannucci@xxxxxxxxxxxx
 4800 Oak Grove Drive,                   http://genesis.jpl.nasa.gov
 Pasadena, CA 91109
---------------------------- Info -----------------------------
List Post: <mailto:macosx-emacs@xxxxxxxxxxxxxxxxx>
List Archives: <http://dir.gmane.org/gmane.emacs.macintosh.osx>