Failing `import numpy.distutils.core` with python-numpy package installed

In the source folder for http://code.google.com/p/netcdf4-python/ running `python setup.py install` as described in the README file fails with:

  logi@magni:~/python-lib/netCDF4-0.9.9$ python setup.py install
  Traceback (most recent call last):
    File "setup.py", line 2, in <module>
      from numpy.distutils.core import setup, Extension
    File "/usr/lib/python2.7/dist-packages/numpy/distutils/core.py", line 25, in <module>
      from numpy.distutils.command import config, config_compiler, \
    File "/usr/lib/python2.7/dist-packages/numpy/distutils/command/build_ext.py", line 16, in <module>
      from numpy.distutils.system_info import combine_paths
    File "/usr/lib/python2.7/dist-packages/numpy/distutils/system_info.py", line 205, in <module>
      p = sp.Popen(["dpkg-architecture", "-qDEB_HOST_MULTIARCH"], stdout=sp.PIPE)
    File "/usr/lib/python2.7/subprocess.py", line 679, in __init__
      errread, errwrite)
    File "/usr/lib/python2.7/subprocess.py", line 1249, in _execute_child
      raise child_exception
  OSError: [Errno 2] No such file or directory

This has worked on Ubuntu 11.10, an earlier iteration of 12.04 (although the exact package version number is lost in the mists of time) and a Debian testing.

Running the same line interactively, either identically as `from numpy.distutils.core import setup, Extension` or as `import numpy.distutils.core` fails in the same way.

To verify:
  logi@magni:~/python-lib/netCDF4-0.9.9$ file /usr/lib/python2.7/dist-packages/numpy/core/__init__.py
  /usr/lib/python2.7/dist-packages/numpy/core/__init__.py: symbolic link to `../../../../../share/pyshared/numpy/core/__init__.py'
  logi@magni:~/python-lib/netCDF4-0.9.9$ file /usr/lib/python2.7/dist-packages/numpy/core/../../../../../share/pyshared/numpy/core/__init__.py
  /usr/lib/python2.7/dist-packages/numpy/core/../../../../../share/pyshared/numpy/core/__init__.py: Python script, ASCII text executable

  logi@magni:~/python-lib/netCDF4-0.9.9$ python
  Python 2.7.3rc1 (default, Mar 10 2012, 08:44:28)
  [GCC 4.6.3] on linux2

  logi@magni:~/python-lib/netCDF4-0.9.9$ dpkg --list *numpy*
  [headers]
  ii python-numpy 1:1.6.1-5ubuntu1 Numerical Python adds a fast array facility to the Python language
  [uninstalled packages]