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In GNU Emacs 21.4.1 (x86_64-redhat-linux-gnu, X toolkit, Xaw3d scroll bars)
 of 2005-05-18 on dolly.build.redhat.com
configured using `configure  --build=x86_64-redhat-linux 
--host=x86_64-redhat-linux --target=x86_64-redhat-linux-gnu 
--program-prefix= --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin 
--sbindir=/usr/sbin --sysconfdir=/etc --datadir=/usr/share 
--includedir=/usr/include --libdir=/usr/lib64 --libexecdir=/usr/libexec 
--localstatedir=/var --sharedstatedir=/usr/com --mandir=/usr/share/man 
--infodir=/usr/share/info --with-pop --with-sound'
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.UTF-8
  locale-coding-system: utf-8
  default-enable-multibyte-characters: t

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:

Configure emacs to use matlab mode on .m files (lines from .emacs follow):
-----------------------------
; matlab-mode stuff
(autoload 'matlab-mode "matlab" "Enter Matlab mode." t)
(setq auto-mode-alist (cons '("\\.m\\'" . matlab-mode) auto-mode-alist))
(autoload 'matlab-shell "matlab" "Interactive Matlab mode." t)
-----------------------------

Start emacs
Load file tst.m (attached to this message). Observe matlab mode getting 
loaded (.el file attached)
Try to add a few empty lines to the end of the file.
See how emacs starts consuming 100% of cputime and doesn't respond to 
any keystrokes.



Recent input:
M-x r e <tab> p o <tab> <backspace> <backspace> <backspace>
<backspace> r e <tab> p o <tab> r <tab> <return>

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