Cool, I will have to try this out. I have also been using pydev with Eclipse and I have found it very usefull to set up django-admin.py as an "external tool". That way I can run the django-admin.py runserver for a number of different django projects, all from within Eclipse.
This has worked great for running the server, but your build.xml looks like it does a good job of handling almost everything django-admin.py can do.
