pip install virtualenvwrapper finds old pip packages before most recently installed
When using pip (1.5.2) installed in /usr/local/bin/pip and running the command line:
pip install virtualenvwrapper
It finds and older version of pip (0.3.1) in /usr/shared/pyshared/ and aborts install, although a newer version pip is installed in /usr/local/lib, but is not given precendence. /usr/local/bin is ahead of /usr/bin in PATH and the correct pip (1.5.2) is executed.
My workaround was to force the system-installed (old) version of pip to not be installed by uninstalling the python-pip package (Ubuntu 10.04) and using easy_install to install pip.