bug#2689: 23.0.91; Can't customize whitespace-display-mappings: "This field should contain a single character"

1. Open emacs -Q, with Emacs from CVS from right now
2. M-x customize-variable RET whitespace-display-mappings RET
3. Imagine you want to change the $ (which represents newline) to / (or anything else) and do this change
4. Try to save changes for current session

  You get this error: "This field should contain a single character". And the change isn't saved.

  I don't attach the back trace because it's huge and doesn't add more information.


Thanks

-- Daniel


In GNU Emacs 23.0.91.5 (i686-pc-linux-gnu, GTK+ Version 2.14.4)
 of 2009-03-16 on CPU107
Windowing system distributor `The X.Org Foundation', version 11.0.10502000
configured using `configure  '--prefix=/opt/dc''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: ca_ES.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default-enable-multibyte-characters: t