The line 
            s = bytearray([0o200])
would be a good point to start.

Pasting relevant output from "report-emacs-bug":

In GNU Emacs 23.3.3 (x86_64-pc-linux-gnu, GTK+ Version 2.24.6)
 of 2011-09-28 on ndl
Windowing system distributor `The X.Org Foundation', version 11.0.11004000
configured using `configure  '--prefix=/usr' '--build=x86_64-pc-linux-gnu' '--host=x86_64-pc-linux-gnu' '--mandir=/usr/share/man' '--infodir=/usr/share/info' '--datadir=/usr/share' '--sysconfdir=/etc' '--localstatedir=/var/lib' '--libdir=/usr/lib64' '--program-suffix=-emacs-23' '--infodir=/usr/share/info/emacs-23' '--with-crt-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/../../../../lib64' '--with-gameuser=games' '--without-hesiod' '--without-kerberos' '--without-kerberos5' '--with-gpm' '--with-dbus' '--with-sound' '--with-x' '--without-ns' '--without-gconf' '--with-toolkit-scroll-bars' '--with-gif' '--with-jpeg' '--with-png' '--with-rsvg' '--with-tiff' '--with-xpm' '--with-xft' '--with-libotf' '--with-m17n-flt' '--with-x-toolkit=gtk' 'build_alias=x86_64-pc-linux-gnu' 'host_alias=x86_64-pc-linux-gnu' 'CFLAGS=-O2 -pipe -march=core2 -fno-strict-aliasing' 'LDFLAGS=-Wl,-O1 -Wl,--as-needed' 'CPPFLAGS=''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: C
  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.utf8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Python

Minor modes in effect:
  reveal-mode: t
  shell-dirtrack-mode: t
  yas/global-mode: t
  yas/minor-mode: t
  semantic-tag-folding-mode: t
  semantic-decoration-mode: t
  semantic-mru-bookmark-mode: t
  semantic-idle-summary-mode: t
  semantic-idle-scheduler-mode: t
  senator-minor-mode: t
  test-case-mode: t
  test-case-global-mode: t
  highlight-symbol-mode: t
  hi-lock-mode: t
  nxhtml-menu-mode: t
  nxhtml-tag-do-also: t
  popcmp-group-alternatives: t
  popcmp-short-help-beside-alts: t
  mlinks-active-links: t
  rngalt-minimal-validation-header: t
  rngalt-display-validation-header: t
  global-auto-complete-mode: t
  auto-complete-mode: t
  eproject-mode: t
  winpoint-mode: t
  flymake-mode: t
  autopair-mode: t
  show-paren-mode: t
  recentf-mode: t
  minibuffer-electric-default-mode: t
  gud-tooltip-mode: t
  global-hl-line-mode: t
  display-time-mode: t
  desktop-save-mode: t
  cua-mode: t
  auto-insert-mode: t
  semantic-highlight-func-mode: t
  semantic-stickyfunc-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  size-indication-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
/home/gbr/.emacs.d/nxhtml/util/web-vcs hides /home/gbr/.emacs.d/nxhtml/web-vcs
/home/gbr/.emacs.d/nxhtml/util/vline hides ~/.emacs.d/vline
~/.emacs.d/emacs-goodies-el/browse-kill-ring hides ~/.emacs.d/browse-kill-ring
~/.emacs.d/emacs-goodies-el/browse-kill-ring hides /usr/share/emacs/site-lisp/browse-kill-ring/browse-kill-ring
~/.emacs.d/color-moccur hides /usr/share/emacs/site-lisp/color-moccur/color-moccur
~/.emacs.d/dropdown-list hides /usr/share/emacs/site-lisp/dropdown-list/dropdown-list
~/.emacs.d/tabbar hides /usr/share/emacs/site-lisp/emhacks/tabbar
~/.emacs.d/emacs-goodies-el/filladapt hides /usr/share/emacs/site-lisp/filladapt/filladapt
~/.emacs.d/grep-edit hides /usr/share/emacs/site-lisp/grep-edit/grep-edit
~/.emacs.d/redo hides /usr/share/emacs/site-lisp/redo/redo
/home/gbr/.emacs.d/nxhtml/util/chart hides /usr/share/emacs/site-lisp/cedet/eieio/chart
/home/gbr/.emacs.d/nxhtml/util/htmlfontify hides /usr/share/emacs/23.3/lisp/htmlfontify
/usr/share/emacs/site-lisp/cedet/common/ezimage hides /usr/share/emacs/23.3/lisp/ezimage
/usr/share/emacs/site-lisp/cedet/speedbar/dframe hides /usr/share/emacs/23.3/lisp/dframe
/home/gbr/.emacs.d/nxhtml/util/hfy-cmap hides /usr/share/emacs/23.3/lisp/hfy-cmap
/usr/share/emacs/site-lisp/cedet/speedbar/speedbar hides /usr/share/emacs/23.3/lisp/speedbar
~/.emacs.d/custom hides /usr/share/emacs/23.3/lisp/custom
/usr/share/emacs/site-lisp/cedet/speedbar/sb-image hides /usr/share/emacs/23.3/lisp/sb-image
~/.emacs.d/css-mode hides /usr/share/emacs/23.3/lisp/textmodes/css-mode
~/.emacs.d/rst hides /usr/share/emacs/23.3/lisp/textmodes/rst
~/.emacs.d/python hides /usr/share/emacs/23.3/lisp/progmodes/python
/home/gbr/.emacs.d/nxhtml/util/org-freemind hides /usr/share/emacs/23.3/lisp/org/org-freemind
/usr/share/emacs/site-lisp/cedet/eieio/eieio-comp hides /usr/share/emacs/23.3/lisp/emacs-lisp/eieio-comp
/usr/share/emacs/site-lisp/cedet/eieio/eieio-base hides /usr/share/emacs/23.3/lisp/emacs-lisp/eieio-base
/usr/share/emacs/site-lisp/cedet/eieio/eieio-opt hides /usr/share/emacs/23.3/lisp/emacs-lisp/eieio-opt
/usr/share/emacs/site-lisp/cedet/eieio/eieio-custom hides /usr/share/emacs/23.3/lisp/emacs-lisp/eieio-custom
/usr/share/emacs/site-lisp/cedet/eieio/eieio-speedbar hides /usr/share/emacs/23.3/lisp/emacs-lisp/eieio-speedbar
/home/gbr/.emacs.d/nxhtml/util/chart hides /usr/share/emacs/23.3/lisp/emacs-lisp/chart
/usr/share/emacs/site-lisp/cedet/eieio/eieio hides /usr/share/emacs/23.3/lisp/emacs-lisp/eieio
/usr/share/emacs/site-lisp/cedet/eieio/eieio-datadebug hides /usr/share/emacs/23.3/lisp/emacs-lisp/eieio-datadebug
/usr/share/emacs/site-lisp/cedet/common/pulse hides /usr/share/emacs/23.3/lisp/cedet/pulse
/usr/share/emacs/site-lisp/cedet/common/cedet-idutils hides /usr/share/emacs/23.3/lisp/cedet/cedet-idutils
/usr/share/emacs/site-lisp/cedet/semantic/semantic hides /usr/share/emacs/23.3/lisp/cedet/semantic
/usr/share/emacs/site-lisp/cedet/common/data-debug hides /usr/share/emacs/23.3/lisp/cedet/data-debug
/usr/share/emacs/site-lisp/cedet/ede/ede hides /usr/share/emacs/23.3/lisp/cedet/ede
/usr/share/emacs/site-lisp/cedet/common/cedet hides /usr/share/emacs/23.3/lisp/cedet/cedet
/usr/share/emacs/site-lisp/cedet/common/cedet-global hides /usr/share/emacs/23.3/lisp/cedet/cedet-global
/usr/share/emacs/site-lisp/cedet/common/mode-local hides /usr/share/emacs/23.3/lisp/cedet/mode-local
/usr/share/emacs/site-lisp/cedet/common/cedet-files hides /usr/share/emacs/23.3/lisp/cedet/cedet-files
/usr/share/emacs/site-lisp/cedet/common/inversion hides /usr/share/emacs/23.3/lisp/cedet/inversion
/usr/share/emacs/site-lisp/cedet/srecode/srecode hides /usr/share/emacs/23.3/lisp/cedet/srecode
/usr/share/emacs/site-lisp/cedet/common/cedet-cscope hides /usr/share/emacs/23.3/lisp/cedet/cedet-cscope

Features:
(shadow sort message idna sendmail ecomplete rfc822 mml mml-sec
password-cache mm-decode mm-bodies mm-encode mailcap mail-parse rfc2231
rfc2047 rfc2045 qp ietf-drums mailabbrev nnheader gnus-util netrc
gmm-utils mailheader canlock sha1 hex-util hashcash mail-utils emacsbug
wisent-javascript-jv wisent-javascript-jv-wy semantic-java semantic-doc
js json etags fuzzy uni-input quail haskell-cabal haskell-font-lock
haskell-decl-scan haskell-doc inf-haskell haskell-mode newcomment
mail-extr eieio-opt dircolors ede-linux ede-emacs ede-cpp-root
semantic-dep copyright time-stamp vc-git semantic-tag-ls
semanticdb-typecache semantic-tag-write multi-isearch windmove
semantic-tag-file semantic-find semanticdb-file cedet-files
semantic-edit wisent-python semantic-decorate-include semanticdb-find
semanticdb-ref wisent-python-wy semantic-wisent wisent reveal ipython
executable show-wspace python-mode hippie-exp ansi-color shell
semantic-el semantic-bovine bovine-debug semantic-debug yasnippet
semantic-tag-folding semantic-decorate-mode semantic-decorate pulse
semantic-mru-bookmark semanticdb-mode semantic-idle senator which-func
semantic-imenu semantic-sb test-case-mode fringe-helper rainbow-mode
shell-pop highlight-beyond-fill-column highlight-symbol hi-lock
thingatpt nxhtml-autostart nxhtml-autoload moz majmodpri vc-hg unsafep
nxhtml-menu udev-rinari udev-ecb udev flymake-js css-color nxhtml-mode
html-quote tidy-xhtml ediff-merg ediff-diff ediff-wind ediff-help
ediff-util ediff-mult ediff-init ediff html-imenu imenu loadhist popcmp
xhtml-help mlinks url-expand url-util url-methods html-toc xml fupd
html-pagetoc foldit appmenu-fold appmenu mumamo sgml-mode rngalt
rng-nxml nxml-mode nxml-outln nxml-rap nxml-glyph rng-valid rng-loc
rng-uri rng-parse nxml-parse rng-match rng-dt rng-util rng-pttrn nxml-ns
nxml-util nxml-enc xmltok help-mode view flyspell ispell fold-dwim
hideshow html-upl html-site url-parse url-vars mm-util mail-prsvr
ourcomments-util org org-footnote org-src org-list org-faces org-compat
org-macs time-date noutline outline bookmark pp apropos ffip gimpedit
cus-edit web-vcs rx web-autoload nxhtml-base dabbrev-highlight dabbrev
auto-complete-config auto-complete popup pos-tip fastnav eproject-gb
full-ack eproject-extras ibuf-macs ibuf-ext ibuffer iswitchb eproject
esh-var esh-io esh-cmd esh-ext esh-proc esh-arg eldoc esh-groups eshell
esh-module esh-mode esh-util repeatable dubious-paragraphs winpoint rrc
tabbar flymake-cursor browse-kill-ring filladapt session grep-edit
color-moccur bar-cursor diminish flymake find-file cc-mode cc-fonts
cc-menus cc-cmds glsl-mode cc-styles cc-align cc-engine cc-vars cc-defs
autopair wdired dired regexp-opt term disp-table ehelp electric
generic-x edmacro kmacro ffap saveplace uniquify paren recentf
tree-widget minibuf-eldef ido icomplete gud easy-mmode grep hl-line time
desktop delsel cua-base autoinsert cus-start cus-load server site-gentoo
ecb-autoloads hs-lint compile comint ring gdiff-setup vc vc-dispatcher
cedet cedet-contrib-load contrib-loaddefs cogre-load cogre-loaddefs
speedbar-load speedbar-loaddefs ede-load ede-loaddefs ede-speedbar
ede-files ede ede-base ede-auto eieio-speedbar semantic-ia-sb
semantic-analyze semantic-scope semantic-analyze-fcn semantic-sort
semanticdb-el semanticdb semantic-ctxt semantic-format
semantic-util-modes semantic-util semantic semantic-lex semantic-tag
working fame speedbar sb-image ezimage dframe easymenu assoc
eieio-custom wid-edit ede-source eieio-base srecode-load srecode
srecode-loaddefs semantic-load semantic-fw semantic-loaddefs mode-local
find-func derived eieio-load eieio-loaddefs cedet-load cedet-compat
cedet-loaddefs eieio warnings advice help-fns advice-preload byte-opt
bytecomp byte-compile cl cl-19 inversion tex-site auto-loads tooltip
ediff-hook vc-hooks lisp-float-type mwheel x-win x-dnd font-setting
tool-bar dnd fontset image fringe lisp-mode register page menu-bar
rfn-eshadow timer select scroll-bar mldrag mouse jit-lock font-lock
syntax facemenu font-core frame cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese hebrew greek
romanian slovak czech european ethiopic indian cyrillic chinese
case-table epa-hook jka-cmpr-hook help simple abbrev loaddefs button
minibuffer faces cus-face files text-properties overlay md5 base64
format env code-pages mule custom widget hashtable-print-readable
backquote make-network-process dbusbind font-render-setting gtk
x-toolkit x multi-tty emacs)