No api proxy found for service "rdbms"

Hi,

I'm developing an app using the python 2.7 runtime and django-nonrel (which, as I understand, is the currently recommended way to build Django apps for App Engine). I'd like to access a Google Cloud SQL instance from my app. Note that I am not trying to replace Django's database. I simply want to retrieve data from Google Cloud SQL independent of Django.

I got a simple test to work when deployed, but I get the following error from the development server:

  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/api/apiproxy_stub_map.py", line 301, in MakeSyncCall

    assert stub, 'No api proxy found for service "%s"' % service

AssertionError: No api proxy found for service "rdbms"

Note that, since my app is built using Django, I need to launch the development server via './manage.py runserver' instead of './dev_appserver.py'. 

My development machine is running Mac OSX 10.7.2, MySQL 5.5.18, and I've installed MySQL-python-1.2.3. I can successfully import MySLQdb from an interactive python interpreter. A last piece of information: when the development server starts up, it throws the following warning:

WARNING  2011-12-13 14:03:14,366 py_zipimport.py:139] Can't open zipfile /Library/Python/2.7/site-packages/MySQL_python-1.2.3-py2.7-macosx-10.7-intel.egg: IOError: [Errno 13] file not accessible: '/Library/Python/2.7/site-packages/MySQL_python-1.2.3-py2.7-macosx-10.7-intel.egg'

Any ideas about what I'm missing?

Thanks!

Leo