What to do when pip does not install latest version

I was trying to pip upgrade django in on my development box. Imagine my confusion when pip install django –upgrade upgraded my 1.3 alpha 1 version to version 1.2.3, breaking all my 1.3 specific code. There seems to be an issue with pointers in the virtual environment build/ directory. To fix the issue, all you need to do is remove the build/django/ folder and rerun pip install django –upgrade you will get the version you expect.