File incorrectly stored to disk

[Dr. Matthias H. Fröhlich]

Greetings.

I encountered the following behaviour in 
    GNU Emacs 21.2.1 (i386-msvc-nt4.0.1381) of 2002-03-19 on buffy
that might be considered a bug. I run Emacs on an Intel-PC with 
Windows NT 4 (German version) with SP 5.

I newly created file a.txt and typed some text in it, then stored it to a
network file system. I buried the buffer visiting the file (C-x k) and 
checked the size of the file with dired. I then opened the file again and 
deleted some of the text and changed a few characters. I saved again, and 
buried the buffer. When I now check the size of the file (e.g. with 'g' in 
dired), it appears unchanged. When I open the file again, I can see the 
changed contents, but there are additional characters behind the end of my 
last changes. These are exactly the characters, that were there in the first 
version of the file. It appears, as if emacs stored the changed contents at the 
same place of the previous version, without discarding the additional characters
of the (longer) previous version. 

This behavious does only occur on network file systems mounted through 
Banyan-Vines. It does not appear, if I do the same on a network file system 
mounted directly through Windows NT or on a local hard disk. It does also 
appear only, if I disable automatic creation of backup files. So the only 
line in my .emacs file is
    (setq make-backup-files nil)
Apparently this behaviour has something to do with how Emacs and the 
Banyan-Vines file system interact. I also checked the behaviour with other 
editors, namely UltraEdit and Notepad. Both do not exhibit this behaviour, 
even if automatic creation of backup files is disabled with UltraEdit.

It might not even be worthwhile investigating this problem, as some part of 
it definitely needs to be accounted to the Banyan-Vines filesystem, which to 
my knowledge is fairly out of use nowadays. However, there might already be 
some information about this error, so I would be grateful for any information 
about this. Many thanks in advance.

Please do not hesitate to contact me, in case you need some more information

Kind regards 
    Matthias H. Fröhlich

P.S.: Here the output of M-x report-emacs-bug:
In GNU Emacs 21.2.1 (i386-msvc-nt4.0.1381)
 of 2002-03-19 on buffy
configured using `configure --with-msvc (12.00)'
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: DEU
  locale-coding-system: iso-latin-1
  default-enable-multibyte-characters: t

----------------------------------------------------------------------
Dr. Matthias H. Fröhlich                       Tel.: +49/2233/928939-1
Frankenstraße 29                                Fax: +49/2233/928939-2
D-50354 Hürth                                   Mobil: +49/175/3539965
                   E-Mail: Dr.M.H.Froehlich@ieee.org
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