strange behaviour of "//" in open file names

[Torsten Bronger]

When I open a file with C-x C-f I have to enter its name in the minibuffer.  If
its name contains double slashs "//", everything before them is printed in grey
(my global standard colour is orange).  Additionally, a C-a doesn't go to the
first character in the file path but to the most recent double slash (if the
cursor was behind it).

In GNU Emacs 22.0.50.7 (i686-pc-linux-gnu)
 of 2006-02-02 on wilson
X server distributor `The Cygwin/X Project', version 11.0.60802000
configured using `configure '--prefix=/usr/local/' 
'--infodir=/usr/local/share/info/' '--mandir=/usr/local/share/man/' 
'--with-x-toolkit=no''

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: de_DE.UTF-8
  locale-coding-system: utf-8
  default-enable-multibyte-characters: t

Major mode: Python

Minor modes in effect:
  global-auto-revert-mode: t
  desktop-save-mode: t
  auto-compression-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  unify-8859-on-decoding-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  line-number-mode: t

Recent input:
<down> <down> M-< C-s b u g C-s <left> 9 <return> <down> 
<down> <down> <down> <down> <down> <down> <down> <return> 
SPC SPC <backspace> <backspace> SPC SPC <backspace> 
<up> <up> <return> <down> <return> <return> <return> 
<return> <return> <return> <return> <return> <return> 
<return> <return> <return> <return> <return> <return> 
<return> <return> <return> <return> <return> <return> 
<return> <return> <return> <return> a C-x r i s <down> 
<down> <down> <down> <down> <down> <up> C-x r i b <down> 
<down> <down> <down> <down> <down> <up> C-SPC <down> 
<down> <down> <down> C-w C-x C-g C-c C-d q q M-x r 
e p o <tab> r <tab> <return>

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