It looks like subprocess.getstatusoutput on 3.2a1 tries to coerce to UTF-8, which fails when dealing with bytes. This demonstrates the behavior nearly all the time for me on Ubuntu 10.04:

>>> import subprocess
>>> subprocess.getstatusoutput('dd if=/dev/random bs=1K count=1')

Here's the tracebacks from a few runs:

>>> subprocess.getstatusoutput('dd if=/dev/random bs=1K count=1')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.2/subprocess.py", line 585, in getstatusoutput
    text = pipe.read()
  File "/usr/local/lib/python3.2/codecs.py", line 300, in decode
    (result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf8' codec can't decode byte 0xcb in position 3: invalid continuation byte
>>> subprocess.getstatusoutput('dd if=/dev/random bs=1K count=1')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.2/subprocess.py", line 585, in getstatusoutput
    text = pipe.read()
  File "/usr/local/lib/python3.2/codecs.py", line 300, in decode
    (result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf8' codec can't decode byte 0xe4 in position 2: invalid continuation byte
>>> subprocess.getstatusoutput('dd if=/dev/random bs=1K count=1')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.2/subprocess.py", line 585, in getstatusoutput
    text = pipe.read()
  File "/usr/local/lib/python3.2/codecs.py", line 300, in decode
    (result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf8' codec can't decode byte 0xac in position 0: invalid start byte
>>> subprocess.getstatusoutput('dd if=/dev/random bs=1K count=1')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.2/subprocess.py", line 585, in getstatusoutput
    text = pipe.read()
  File "/usr/local/lib/python3.2/codecs.py", line 300, in decode
    (result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf8' codec can't decode byte 0xf1 in position 0: invalid continuation byte
>>> 

And here's the version info:

Python 3.2a1 (r32a1:83318, Aug 13 2010, 22:32:03) 
[GCC 4.4.3] on linux2
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