Error in pip installation

virtualenv_with_sudo-iu

root@debian-32:~# sudo -iu git virtualenv /opt/gitosis/test
New python executable in /opt/gitosis/test/bin/python
Installing setuptools.............done.
Installing pip...............done.

root@debian-32:~# sudo -iu git pwd
/opt/gitosis

virtualenv_with_sudo-u

root@debian-32:~# sudo -u git virtualenv /opt/gitosis/test
New python executable in /opt/gitosis/test/bin/python
Installing setuptools............done.
Installing pip.........
  Complete output from command /opt/gitosis/test/bin/python /opt/gitosis/test/bin/easy_install /usr/local/lib/pytho...ort/pip-1.0.2.tar.gz:
  Processing pip-1.0.2.tar.gz
Running pip-1.0.2/setup.py -q bdist_egg --dist-dir /tmp/easy_install-AKtDJg/pip-1.0.2/egg-dist-tmp-5mX4km
warning: no files found matching '*.html' under directory 'docs'
warning: no previously-included files matching '*.txt' found under directory 'docs/_build'
no previously-included directories found matching 'docs/_build/_sources'
error: /root: Permission denied
----------------------------------------
...Installing pip...done.
Traceback (most recent call last):
  File "/usr/local/bin/virtualenv", line 9, in <module>
    load_entry_point('virtualenv==1.6.4', 'console_scripts', 'virtualenv')()
  File "/usr/local/lib/python2.6/dist-packages/virtualenv-1.6.4-py2.6.egg/virtualenv.py", line 810, in main
    never_download=options.never_download)
  File "/usr/local/lib/python2.6/dist-packages/virtualenv-1.6.4-py2.6.egg/virtualenv.py", line 912, in create_environment
    install_pip(py_executable, search_dirs=search_dirs, never_download=never_download)
  File "/usr/local/lib/python2.6/dist-packages/virtualenv-1.6.4-py2.6.egg/virtualenv.py", line 648, in install_pip
    filter_stdout=_filter_setup)
  File "/usr/local/lib/python2.6/dist-packages/virtualenv-1.6.4-py2.6.egg/virtualenv.py", line 878, in call_subprocess
    % (cmd_desc, proc.returncode))
OSError: Command /opt/gitosis/test/bin/python /opt/gitosis/test/bin/easy_install /usr/local/lib/pytho...ort/pip-1.0.2.tar.gz failed with error code 1

root@debian-32:~# sudo -u git pwd
/root