modes that you want whitespaces checked in by adding something like the
following to your `.emacs':
-\(setq whitespace-modes (cons 'my-mode (cons 'my-other-mode
+\(setq whitespace-modes (cons \\='my-mode (cons \\='my-other-mode
whitespace-modes))\)
Or, alternately, you can use the Emacs `customize' command to set this."