Issue1351

The following could be reproduced both on Windows XP and Windows Vista,
using Jython 2.5rc2:

C:\stuff\jython\jython-2.5rc2>jython
Jython 2.5rc2 (Release_2_5rc2:6341, May 11 2009, 17:07:28)
[Java HotSpot(TM) Client VM (Sun Microsystems Inc.)] on java1.6.0_13
Type "help", "copyright", "credits" or "license" for more information.
>>> import subprocess
>>> import sys
>>> cmd_line = [ sys.executable, '-m', 'runpy', 'fnordl9203828xyz' ]
>>> subprocess.call(cmd_line)
Traceback (most recent call last):
  #snipped
ImportError: No module named fnordl9203828xyz
>>> subprocess.call(cmd_line, stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
  #running for ever

Turns out this is just an abuse of subprocess.call. The code is 
originally from test_cmd_line, doh

call just wait()s, it doesn't consume the PIPEs we specify. With nothing 
consuming those pipes, the child can deadlock after writing enough 
output to fill the pipe's buffer

The -m runpy fnordXXX was the only trigger because it wrote enough 
output (a traceback) to fill the buffer, and it only happened on Windows 
because Windows has a pretty small pipe buf

The author of subprocess confirms that this is indeed a bad idea here:
http://mail.python.org/pipermail/python-dev/2006-June/066111.html

fixed in r6363