Score files are corrupted

[Jesper Harder]

Score files created by `gamegrid-add-score' in
`shared-game-score-directory' become corrupted after a certain number of
entries.

Steps to reproduce:

* Create an empty score file with, say,

    touch /usr/local/var/games/emacs/foo

* Evaluate

  (dotimes (i 16)
    (gamegrid-add-score "foo" i))

  This works fine.  

* But adding another entry:

   (gamegrid-add-score "foo" 16)

  creates this bogus score file:

foo1
Description: Binary data

* Adding yet another entry:

   (gamegrid-add-score "foo" 17)

  Corrupts the file even more:

foo
Description: Binary data

In GNU Emacs 21.3.50.56 (i686-pc-linux-gnu)
 of 2003-04-22 on defun.localdomain
configured using `configure '--with-gtk''

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.iso88591
  locale-coding-system: iso-latin-1
  default-enable-multibyte-characters: t