bug#4861: 23.1.50; C-u C-x = signals an error: Unknown button type `help-face'

[Sven Joachim]

Pressing C-u C-x = signals an error:

,----
| Debugger entered--Lisp error: (error "Unknown button type `help-face'")
|   signal(error ("Unknown button type `help-face'"))
|   error("Unknown button type `%s'" help-face)
|   make-text-button(57 79 type help-face help-args (font-lock-comment-face))
|   apply(make-text-button 57 79 (type help-face help-args 
(font-lock-comment-face)))
|   insert-text-button("font-lock-comment-face" type help-face help-args 
(font-lock-comment-face))
|   describe-property-list((face font-lock-comment-face fontified t))
|   describe-text-properties-1(144 #<buffer  *text-props*>)
|   describe-text-properties(144 #<buffer  *text-props*>)
|   describe-char(144)
|   what-cursor-position((4))
|   call-interactively(what-cursor-position nil nil)
`----

In GNU Emacs 23.1.50.2 (i486-pc-linux-gnu, GTK+ Version 2.18.3)
 of 2009-11-03 on turtle
Windowing system distributor `The X.Org Foundation', version 11.0.10605000
configured using `configure  '--build=i486-linux-gnu' 
'build_alias=i486-linux-gnu' 'CFLAGS=-DGTK_DISABLE_DEPRECATED -g -O2''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: C
  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: de_DE.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Debugger

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<help-echo> <help-echo> <up> <up> <right> <right> <right> 
C-u C-x = M-x t o g g l e - d e b <tab> e r r <tab> 
<return> C-u C-x = M-x r e p o e <backspace> r t - 
e m <tab> <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
make-text-button: Unknown button type `help-face'
Debug on Error enabled globally
Entering debugger...

Load-path shadows:
None found.

Features:
(shadow mail-extr message ecomplete rfc822 mml mml-sec password-cache
mm-decode mm-bodies mm-encode mailcap mail-parse rfc2231 rfc2047 rfc2045
qp ietf-drums mailabbrev nnheader gnus-util netrc time-date mm-util
mail-prsvr gmm-utils mailheader canlock sha1 hex-util hashcash
mail-utils emacsbug sendmail regexp-opt help-mode easymenu view debug
cus-start cus-load wid-edit descr-text help-fns tooltip ediff-hook
vc-hooks lisp-float-type mwheel x-win x-dnd tool-bar dnd fontset image
fringe lisp-mode register page menu-bar rfn-eshadow timer select
scroll-bar mldrag mouse jit-lock font-lock syntax facemenu font-core
frame cham georgian utf-8-lang misc-lang vietnamese tibetan thai
tai-viet lao korean japanese hebrew greek romanian slovak czech european
ethiopic indian cyrillic chinese case-table epa-hook jka-cmpr-hook help
simple abbrev loaddefs button minibuffer faces cus-face text-properties
overlay md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote make-network-process dbusbind gtk
x-toolkit x multi-tty emacs)