(setq frame-title-format "...") messes up lock files

[Anders Berggren]

Version:
  "GNU Emacs 21.3.1 (sparc-sun-solaris2.8, X toolkit) of 2004-05-04 on sr201"

Reproduce bug:

1. Create an emacs-init-file (mess_up_lock_files.el) containing this one line:
  (setq frame-title-format "%b")

2. Start emacs with
  emacs --no-site-file -q -l mess_up_lock_files.el nonexistent_file.txt

3. Type some letters (this creates the menace .#nonexistent_file.txt@...)

4. Undo until you have no changes. Alternatively, save the buffer.

5. Behold: The .#nonexistent_file.txt@... lock file is still there!

Regards