permission denied error installing django-user-accounts with pip

I'm attempting to install django-user-accounts (http://django-user-accounts.readthedocs.org/en/latest/installation.html) into an application called erickson_prototype. I have cd'd into the webapps/erickson_prototype directory, and installed pip-2.7 using the procedure in Webfaction's docs.

The django-user-accounts documentation says I should run this command:

pip install django-user-accounts

but I have instead followed the instruction in Webfaction's docs (http://docs.webfaction.com/software/python.html#installing-packages-with-pip):

pip-X.Y install --install-option="--install-scripts=$PWD/bin" --install-option="--install-lib=$PWD/lib/pythonX.Y" package

Which I am attempting to run as follows:

pip-2.7 install --install-option="--install-scripts=$PWD/bin" --install-option="--install-lib=$PWD/lib/python2.7" django-user-accounts

Unfortunately, this is the output I get:

Downloading/unpacking django-user-accounts
  Downloading django-user-accounts-1.0b7.tar.gz
Exception:
Traceback (most recent call last):
  File "/home/alanmoore/lib/python2.7/pip-1.2.1-py2.7.egg/pip/basecommand.py", line 107, in main
    status = self.run(options, args)
  File "/home/alanmoore/lib/python2.7/pip-1.2.1-py2.7.egg/pip/commands/install.py", line 256, in run
    requirement_set.prepare_files(finder, force_root_egg_info=self.bundle, bundle=self.bundle)
  File "/home/alanmoore/lib/python2.7/pip-1.2.1-py2.7.egg/pip/req.py", line 1018, in prepare_files
    self.unpack_url(url, location, self.is_download)
  File "/home/alanmoore/lib/python2.7/pip-1.2.1-py2.7.egg/pip/req.py", line 1142, in unpack_url
    retval = unpack_http_url(link, location, self.download_cache, self.download_dir)
  File "/home/alanmoore/lib/python2.7/pip-1.2.1-py2.7.egg/pip/download.py", line 468, in unpack_http_url
    unpack_file(temp_location, location, content_type, link)
  File "/home/alanmoore/lib/python2.7/pip-1.2.1-py2.7.egg/pip/util.py", line 540, in unpack_file
    untar_file(filename, location)
  File "/home/alanmoore/lib/python2.7/pip-1.2.1-py2.7.egg/pip/util.py", line 454, in untar_file
    os.makedirs(location)
  File "/usr/local/lib/python2.7/os.py", line 157, in makedirs
    mkdir(name, mode)
OSError: [Errno 13] Permission denied: '/tmp/pip-build/django-user-accounts'

Storing complete log in /home/alanmoore/.pip/pip.log

Am I doing something wrong here? Should I be specifying a location other than /tmp to get around the permissions issue?