Newbie help!

I'm running Python 2.3 on win XPro. When I try to run
the simple example code I get the following error

Traceback (most recent call last):
line 6, in ?
    from matplotlib.figure import Figure, Subplot
line 19, in ?
    from lines import Line2D_Dispatcher, SolidLine2D,
ImportError: cannot import name Line2D_Dispatcher

I've searched the files for this name,
Line2D_Dispatcher, and can't find it. Is something
missing from my installation?

Barry Drake