subprocess.Popen on Windows

[madpython]

playing with subprocess.Popen on Windows I stumbled into the following
problem:
Python 2.4.3 (#69, Mar 29 2006, 17:35:34)

IDLE 1.1.3

>>> import subprocess
>>> p1=subprocess.Popen("c:\\asd.bat") #works OK
>>> p2=subprocess.Popen("c:\\asd.bat",stdout=subprocess.PIPE)

Traceback (most recent call last):
  File "<pyshell#2>", line 1, in -toplevel-
    p2=subprocess.Popen("c:\\asd.bat",stdout=subprocess.PIPE)
  File "C:\Python24\lib\subprocess.py", line 533, in __init__
    (p2cread, p2cwrite,
  File "C:\Python24\lib\subprocess.py", line 593, in _get_handles
    p2cread = self._make_inheritable(p2cread)
  File "C:\Python24\lib\subprocess.py", line 634, in _make_inheritable
    DUPLICATE_SAME_ACCESS)
TypeError: an integer is required
>>> 
What do I do wrongly?