23.0.60; switch-to-buffer-other-window fails to work

[Michael Welsh Duggan <md5i@cs.cmu.edu>]

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:

`switch-to-buffer-other-window' no longer uses the "other" window.

Using a new emacs via "emacs -Q":
`C-h i' - Displays the *info* buffer
`C-x 4 b RET' - Displays the *scratch* buffer in a second window
`C-x 4 b RET' - Fails to replace the *info* buffer with the *Messages*
                buffer.  Replaces the *scratch* buffer instead.

In GNU Emacs 23.0.60.9 (i686-pc-linux-gnu, GTK+ Version 2.12.10)
 of 2008-06-08 on maru
Windowing system distributor `The X.Org Foundation', version 11.0.10400090
configured using `configure  '--without-toolkit-scroll-bars''

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: en_US.utf8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default-enable-multibyte-characters: t

Major mode: Group

Minor modes in effect:
  gnus-topic-mode: t
  gnus-undo-mode: t
  display-time-mode: t
  shell-dirtrack-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
  line-number-mode: t

Recent input:
SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC 
SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC 
SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC 
SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC 
SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC 
SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC 
SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC 
SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC 
SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC 
SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC SPC 
SPC SPC SPC q C-x 1 M-x g n u s <return> C-n <return> 
C-s w i n d o w C-a SPC C-x o C-x o C-x o C-x b * A 
r <tab> <return> C-x o C-x o N SPC SPC SPC SPC SPC 
SPC SPC SPC n n n n n n n n P C-x 1 C-s C-s C-s C-p 
C-a <escape> < C-s o t h e r C-s C-s C-a C-v Q n p 
<return> C-s m e n u C-a C-n C-p C-p C-p C-p C-p C-p 
C-p d d d d d d d d d d d d d d d d d d d d d d d d 
d d d d d d d d d d d d d d d d d d d d d d d d d d 
d d d d d SPC N N N N N SPC N <help-echo> <help-echo> 
<help-echo> q M-x r e p o r <tab> <return>

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-- 
Michael Welsh Duggan
(md5i@cs.cmu.edu)