As you'll see in the forwarded message below, I originally filed this bug with the nxhtml team, and they asked me to file it against Emacs. I am also able to reproduce this on Kubuntu 10.04 with the emacs-nox package: afineman@hotdog:~$ emacs --version GNU Emacs 23.1.1 Copyright (C) 2009 Free Software Foundation, Inc. GNU Emacs comes with ABSOLUTELY NO WARRANTY. You may redistribute copies of Emacs under the terms of the GNU General Public License. For more information about these matters, see the file named COPYING. afineman@caviar:~$ emacs -q -l ~/elisp/nxhtml/autostart.el Entering the same file as below, I still see a backtrace at the same place, although the trace is slightly different: ------------------------ Debugger entered--Lisp error: (wrong-type-argument listp set-from-style) c-electric-paren(nil) call-interactively(c-electric-paren nil nil) ------------------------ This is the version of nxhtml that I installed: http://ourcomments.org/Emacs/DL/elisp/nxhtml/zip/nxhtml-2.08-100425.zip - Adam ---------- Forwarded message ---------- From: Adam Fineman <663041@bugs.launchpad.net> Date: Mon, Oct 18, 2010 at 8:36 PM Subject: [Bug 663041] [NEW] debugger entered on c-electric-paren To: afineman@afineman.com Public bug reported: afineman@caviar:~$ emacs --version GNU Emacs 22.3.1 Copyright (C) 2008 Free Software Foundation, Inc. GNU Emacs comes with ABSOLUTELY NO WARRANTY. You may redistribute copies of Emacs under the terms of the GNU General Public License. For more information about these matters, see the file named COPYING. afineman@caviar:~$ emacs -q -l nxhtml/autostart.el ------ I open a new file '/tmp/foo.php' and start typing the following: ============= foo foo