South: Unknown command 'migrate'

I'm getting a merciless

$ python manage.py migrate
Unknown command: 'migrate'
Type 'manage.py help' for usage.

I pulled the code from github onto a fresh computer. This code is tested and is working on other computers. The entire code runs fine except for the fact I can't run migrations!

Installed my virtual environment and ran pip install -r requirements.txt. It installs everything, including South. I can check by running

$ python manage.py shell
>>> import south
>>> south.__version__
'0.7.3'

However, when I run the manage.py help, the migrate and schemamigration commands don't appear listed.

I double checked that my settings.py file has 'south' listed under INSTALLED_APPS (I didn't change this file after pulling).

I tried pip uninstall south and then running pip install -r requirements.txt again, but I still get the same error.

Would really appreciate any help!