pip: Unable to find venv/lib/python2.7/config/Makefile

Seems the path is getting mangled. It’s supposed to be looking for /usr/local/myapp/venv/lib/python2.7/config/Makefile but is actually looking for /usr/myapp/venv/lib/python2.7/config/Makefile (dropping the local)

• Ubuntu 12.04
• Python 2.7.3
• pip 1.4
• virtualenv 1.7.1.2

Traceback (most recent call last):
  File "/usr/local/myapp/venv/bin/pip", line 9, in <module>
    load_entry_point('pip==1.4', 'console_scripts', 'pip')()
  File "/usr/local/myapp/venv/local/lib/python2.7/site-packages/distribute-0.6.24-py2.7.egg/pkg_resources.py", line 337, in load_entry_point
    return get_distribution(dist).load_entry_point(group, name)
  File "/usr/local/myapp/venv/local/lib/python2.7/site-packages/distribute-0.6.24-py2.7.egg/pkg_resources.py", line 2279, in load_entry_point
    return ep.load()
  File "/usr/local/myapp/venv/local/lib/python2.7/site-packages/distribute-0.6.24-py2.7.egg/pkg_resources.py", line 1989, in load
    entry = __import__(self.module_name, globals(),globals(), ['__name__'])
  File "/usr/local/myapp/venv/local/lib/python2.7/site-packages/pip/__init__.py", line 11, in <module>
    from pip.vcs import git, mercurial, subversion, bazaar  # noqa
  File "/usr/local/myapp/venv/local/lib/python2.7/site-packages/pip/vcs/subversion.py", line 4, in <module>
    from pip.index import Link
  File "/usr/local/myapp/venv/local/lib/python2.7/site-packages/pip/index.py", line 32, in <module>
    from pip.wheel import Wheel, wheel_ext, wheel_setuptools_support, setuptools_requirement
  File "/usr/local/myapp/venv/local/lib/python2.7/site-packages/pip/wheel.py", line 18, in <module>
    from pip import pep425tags
  File "/usr/local/myapp/venv/local/lib/python2.7/site-packages/pip/pep425tags.py", line 98, in <module>
    supported_tags = get_supported()
  File "/usr/local/myapp/venv/local/lib/python2.7/site-packages/pip/pep425tags.py", line 61, in get_supported
    soabi = sysconfig.get_config_var('SOABI')
  File "/usr/lib/python2.7/sysconfig.py", line 577, in get_config_var
    return get_config_vars().get(name)
  File "/usr/lib/python2.7/sysconfig.py", line 476, in get_config_vars
    _init_posix(_CONFIG_VARS)
  File "/usr/lib/python2.7/sysconfig.py", line 344, in _init_posix
    raise IOError(msg)
IOError: invalid Python installation: unable to open /usr/myapp/venv/lib/python2.7/config/Makefile (No such file or directory)