Possibly bug in matplotlib

matplotlib data path /usr/share/matplotlib
$HOME=/home/nwagner
CONFIGDIR=/home/nwagner/.matplotlib
loaded rc file /home/nwagner/.matplotlib/matplotlibrc
matplotlib version 0.85.cvs
verbose.level helpful
interactive is False
platform is linux2
numerix Numeric 24.2
font search path ['/usr/share/matplotlib']
loaded ttfcache file /home/nwagner/.matplotlib/ttffont.cache
backend GTK version 2.5.3
Traceback (most recent call last):
  File
"/usr/lib/python2.4/site-packages/matplotlib/backends/backend_gtk.py",
line 303, in expose_event
    self._render_figure(self._pixmap, w, h)
  File
"/usr/lib/python2.4/site-packages/matplotlib/backends/backend_gtk.py",
line 291, in _render_figure
    self.figure.draw (self._renderer)
  File "/usr/lib/python2.4/site-packages/matplotlib/figure.py", line
520, in draw
    for a in self.axes: a.draw(renderer)
  File "/usr/lib/python2.4/site-packages/matplotlib/axes.py", line 1410,
in draw
    self.xaxis.draw(renderer)
  File "/usr/lib/python2.4/site-packages/matplotlib/axis.py", line 561,
in draw
    tick.draw(renderer)
  File "/usr/lib/python2.4/site-packages/matplotlib/axis.py", line 160,
in draw
    if self.label1On: self.label1.draw(renderer)
  File "/usr/lib/python2.4/site-packages/matplotlib/text.py", line 850,
in draw
    self._mytext.draw(renderer)
  File "/usr/lib/python2.4/site-packages/matplotlib/text.py", line 336,
in draw
    bbox, info = self._get_layout(renderer)
  File "/usr/lib/python2.4/site-packages/matplotlib/text.py", line 185,
in _get_layout
    w,h = renderer.get_text_width_height(
  File
"/usr/lib/python2.4/site-packages/matplotlib/backends/backend_gdk.py",
line 345, in get_text_width_height
    width, height, fonts = math_parse_s_ft2font(
  File "/usr/lib/python2.4/site-packages/matplotlib/mathtext.py", line
1324, in math_parse_s_ft2font
    expression.parseString( s )
  File "/usr/lib/python2.4/site-packages/matplotlib/pyparsing.py", line
616, in parseString
    loc, tokens = self.parse( instring.expandtabs(), 0 )
  File "/usr/lib/python2.4/site-packages/matplotlib/pyparsing.py", line
558, in parse
    loc,tokens = self.parseImpl( instring, loc, doActions )
  File "/usr/lib/python2.4/site-packages/matplotlib/pyparsing.py", line
1663, in parseImpl
    loc, tokens = self.expr.parse( instring, loc, doActions )
  File "/usr/lib/python2.4/site-packages/matplotlib/pyparsing.py", line
558, in parse
    loc,tokens = self.parseImpl( instring, loc, doActions )
  File "/usr/lib/python2.4/site-packages/matplotlib/pyparsing.py", line
1427, in parseImpl
    raise maxException
matplotlib.pyparsing.ParseException: Expected "\" (at char 0), (line:1,
col:1)

How can I fix this problem ?

Nils