bug#3651: 23.1.50; WoMan getaddrinfo fails: "Invalid search bound (wrong side of point)"

WoMan signals an error on the attached getaddrinfo.3 manpage, here is a
backtrace:

,----
| Debugger entered--Lisp error: (error "Invalid search bound (wrong side of point)")
|   re-search-forward("\\(^\\s *$\\)\\|\\(^\\s +\\)" #<marker (moves after insertion) at 12238 in *WoMan 3 getaddrinfo*> 1)
|   woman2-format-paragraphs(#<marker (moves after insertion) at 12238 in *WoMan 3 getaddrinfo*> 5)
|   woman2-SH(#<marker (moves after insertion) at 12238 in *WoMan 3 getaddrinfo*>)
|   woman2-SS(#<marker (moves after insertion) at 12238 in *WoMan 3 getaddrinfo*>)
|   woman2-roff-buffer()
|   woman-decode-region(1 21603)
|   woman-decode-buffer()
|   woman-process-buffer()
|   woman-really-find-file("/usr/share/man/man3/getaddrinfo.3.gz" t "*WoMan 3 getaddrinfo*")
|   woman-find-file("/usr/share/man/man3/getaddrinfo.3.gz")
|   woman(nil nil)
|   call-interactively(woman nil nil)
`----

In GNU Emacs 23.1.50.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.16.2)
 of 2009-06-22 on turtle
Windowing system distributor `The X.Org Foundation', version 11.0.10601901
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:
<C-f1> g e t a d d r <tab> <return> C-x k <return> 
M-x t o g g l <tab> d e b <tab> e r r o <tab> <return> 
<C-f1> <up> <return> C-x 1 C-x h C-c s C-y C-z C-x 
o M-w C-x o C-y C-x d / t m <tab> <return> g <down> 
<down> <down> <down> <down> <down> g q C-x o q <f7> 
<down> <return> M-x g n u s <return> M-x r e p o <tab> 
r t <tab> <return>

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