 `py-jpython-command-args' are consulted to determine the interpreter
 and arguments to use.
 
-Note that this variable is consulted only the first time that a Python 
-interpreter shell is started during an Emacs session.  After that, use 
+Note that this variable is consulted only the first time that a Python
+mode buffer is visited during an Emacs session.  After that, use
 \\[py-toggle-shells] to change the interpreter shell."
   :type '(choice (const :tag "Python (a.k.a. CPython)" cpython)
 		 (const :tag "JPython" jpython))

      ;; have explicitly turned it off.
      (if (/= tab-width py-indent-offset)
	  (setq indent-tabs-mode nil))
      )))




(defun py-toggle-shells (arg)
  "Toggles between the CPython and JPython shells.

With positive argument ARG (interactively \\[universal-argument]),
uses the CPython shell, with negative ARG uses the JPython shell, and
with a zero argument, toggles the shell.

Programmatically, ARG can also be one of the symbols `cpython' or
`jpython', equivalent to positive arg and negative arg respectively."
  (interactive "P")
  ;; default is to toggle
  (if (null arg)
      (setq arg 0))
  ;; preprocess arg
  (cond
   ((equal arg 0)
    ;; toggle
    (if (string-equal py-which-bufname "Python")
	(setq arg -1)
      (setq arg 1)))
   ((equal arg 'cpython) (setq arg 1))
   ((equal arg 'jpython) (setq arg -1)))
  (let (msg)
    (cond
     ((< 0 arg)
