need help with cryptic error message

[kj]

I have Emacs 22.1, and I'm trying to turn on whitespace-mode.
Nothing I have tried works so far.  It would take a very lengthy
post for me to describe everything I've tried, so I'll just say
that the latest I've done is to put the following in my .emacs
file:

  (autoload 'whitespace-mode "whitespace" "Toggle whitespace visualization." t)

...per the documentation in http://www.emacswiki.org/emacs/WhiteSpace.
When I re-start emacs, visit some file, and try the command

  M-x whitespace-mode

...I get the error message

  Autoloading failed to define function whitespace-mode

...which is almost completely useless.  How can I get more information
on why this defintion failed?

(FWIW, emacs won't let me try the command "whitespace" by itself.
If I attempt it, Emacs simply adds a hyphen to the "whitespace" I
had typed in the minibuffer, and waits for some completion from
me, e.g.  "mode".)

The file whitespace.elc is perfectly accessible in
/usr/share/emacs/22.1/lisp/whitespace.elc.  How can I read the
documentation (and, in particular, the version number) in this file?

Any other words of wisdom would be much appreciated.

Thanks!

Kynn

-- 
NOTE: In my address everything before the first period is backwards;
and the last period, and everything after it, should be discarded.