problem reading data file in stock_demo.py

Hello,

i cant get stock_demo.py to run correctly. it seems
there is a problem reading the data files,
specifically using numarray/Numeric's "fromstring" on
the example data files. the first result below is
with numarray and the second is with Numeric. im
using python 2.3.4 and matplotlib 0.54.2 win32 for
python 2.3.

C:\Matplotlib\matplotlib src\examples>python
stock_demo.py
Traceback (most recent call last):
  File "stock_demo.py", line 7, in ?
    (d1, p1, d2, p2 ) = get_two_stock_data()
  File "C:\Matplotlib\matplotlib
src\examples\data_helper.py", line 12, in
get_two_stock_data
    M1 = fromstring( file('data/%s.dat' % ticker1,
'rb').read(), 'd')
  File
"C:\Python23\Lib\site-packages\numarray\numarraycore.py",
line 358, in fromstring
    raise ValueError("Type size inconsistent with
string length")
ValueError: Type size inconsistent with string length

C:\Matplotlib\matplotlib src\examples>python
stock_demo.py
Traceback (most recent call last):
  File "stock_demo.py", line 7, in ?
    (d1, p1, d2, p2 ) = get_two_stock_data()
  File "C:\Matplotlib\matplotlib
src\examples\data_helper.py", line 12, in
get_two_stock_data
    M1 = fromstring( file('data/%s.dat' % ticker1,
'rb').read(), 'd')
ValueError: string size must be a multiple of element
size

since the example data files are binary, i cant figure
out how to investigate what may be happening with
them.

Is there something else i should be doing?

Tks vm,

Tom