bug#3228: 23.0.93; GTK font selection: asked for Courier, got Nimbus

I have set up the following X resources for Emacs:

Emacs.FontBackend: xft, x
Emacs.font:-adobe-courier-medium-r-normal--*-120-*-*-m-*-iso10646-1

This works okay, as can be seen with `C-u C-x =' :

,----
|         character: S (83, #o123, #x53)
| preferred charset: ascii (ASCII (ISO646 IRV))
|        code point: 0x53
|            syntax: w 	which means: word
|          category: .:Base, a:ASCII, l:Latin, r:Roman
|       buffer code: #x53
|         file code: #x53 (encoded by coding system utf-8-unix)
|           display: by this font (glyph code)
|     xft:-Adobe-Courier-normal-normal-normal-*-17-*-*-*-m-100-iso10646-1 (#x35)
`----

But choosing "Courier 12" from the GTK font selection dialog gives me
another font, and an extremely ugly one:

,----
|         character: S (83, #o123, #x53)
| preferred charset: ascii (ASCII (ISO646 IRV))
|        code point: 0x53
|            syntax: w 	which means: word
|          category: .:Base, a:ASCII, l:Latin, r:Roman
|       buffer code: #x53
|         file code: #x53 (encoded by coding system utf-8-unix)
|           display: by this font (glyph code)
|     x:-urw-nimbus mono l-regular-r-normal--17-123-100-100-p-100-iso8859-1 (#x53)
`---- ^^^^^^^^^^^^^

In GNU Emacs 23.0.93.2 (x86_64-unknown-linux-gnu, GTK+ Version 2.16.1)
 of 2009-05-06 on turtle
Windowing system distributor `The X.Org Foundation', version 11.0.10601000
configured using `configure  '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: Group

Minor modes in effect:
  gnus-undo-mode: t
  display-time-mode: t
  auto-image-file-mode: t
  show-paren-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  temp-buffer-resize-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <menu-bar> 
<options> <menu-set-font> <up> <up> <right> <right> 
<right> C-u C-x = C-x o C-c r C-x o <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <menu-bar> 
<options> <menu-set-font> C-u C-x = C-x o C-c r C-x 
1 M-x g n u s <return> <down> <down> <down> <down> 
<down> <down> <down> <down> <down> <down> <down> <down> 
<down> <down> <down> <down> <up> <up> <up> M-x r e 
p o <tab> r t - e m <tab> <return>

Recent messages:
Opening nnfolder server on archive...done
Reading active file from archive via nnfolder...done
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No new newsgroups
Checking new news...
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