problem using matplotlib

I just installed the latest matplotlib and wanted to run
the first example from the homepage.
But I got:

Python 2.3.3 (#2, Mar 12 2004, 16:09:39)
[GCC 3.2.2 (Mandrake Linux 9.1 3.2.2-3mdk)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import matplotlib.matlab
Numeric import failed... trying numarray.
Traceback (most recent call last):
   File "<stdin>", line 1, in ?
   File "/usr/local/lib/python2.3/site-packages/matplotlib/", line 126, in ?
     from axes import Axes
   File "/usr/local/lib/python2.3/site-packages/matplotlib/", line 244, in ?
     class Axes(Artist):
   File "/usr/local/lib/python2.3/site-packages/matplotlib/", line 814, in Axe s
     def imshow(self, X, cmap = Grayscale(256)):
   File "/usr/local/lib/python2.3/site-packages/matplotlib/", line 213, in _ _init__
     Colormap.__init__(self, N, 'gray')
   File "/usr/local/lib/python2.3/site-packages/matplotlib/", line 96, in __ init__
   File "/usr/local/lib/python2.3/site-packages/matplotlib/", line 118, in _ make_red = 1.0/self.N*arange(self.N, typecode=Float)
TypeError: arange() got an unexpected keyword argument 'typecode'

Any suggestions?