get_sfnt_name

Hi. Am a new user, running Enthought Python23 on Windows XP. I am trying to run the simple_plot and subplot_demo.py examples. I am getting the error message below regardless of which backend I use. Am I doing something wrong in the configuration?
Thanks
Eli

C:\Python23\Lib\site-packages\matplotlib>python subplot_demo.py
Traceback (most recent call last):
   File "subplot_demo.py", line 1, in ?
     from matplotlib.matlab import *
   File "C:\Python23\Lib\site-packages\matplotlib\matlab.py", line 142, in ?
     from axes import Axes
   File "C:\Python23\Lib\site-packages\matplotlib\axes.py", line 10, in ?
     from axis import XTick, YTick, XAxis, YAxis
   File "C:\Python23\Lib\site-packages\matplotlib\axis.py", line 20, in ?
     from font_manager import FontProperties
   File "C:\Python23\Lib\site-packages\matplotlib\font_manager.py", line 918, in ?
     fontManager = FontManager()
   File "C:\Python23\Lib\site-packages\matplotlib\font_manager.py", line 763, in __init__
     self.ttfdict = createFontDict(self.ttffiles)
   File "C:\Python23\Lib\site-packages\matplotlib\font_manager.py", line 410, in createFontDict
     prop = ttfFontProperty(font)
   File "C:\Python23\Lib\site-packages\matplotlib\font_manager.py", line 224, in ttfFontProperty
     sfnt2 = font.get_sfnt_name(2)
AttributeError: get_sfnt_name