"App with label forum could not be found" when running migrate

installation
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I've successfully run startforum and the database sync. Now, when trying to run the migrate forum command, I get the following

C:\saskbot3>python manage.py migrate forum
C:\Python26\lib\site-packages\MySQLdb\__init__.py:34: DeprecationWarning: the sets module is deprecated
  from sets import ImmutableSet
Traceback (most recent call last):
  File "manage.py", line 11, in <module>
    execute_manager(settings)
  File "C:\Python26\lib\site-packages\django-1.1.2-py2.6.egg\django\core\management\__init__.py", line 362, in execute_manager
    utility.execute()
  File "C:\Python26\lib\site-packages\django-1.1.2-py2.6.egg\django\core\management\__init__.py", line 303, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "C:\Python26\lib\site-packages\django-1.1.2-py2.6.egg\django\core\management\base.py", line 195, in run_from_argv
    self.execute(*args, **options.__dict__)
  File "C:\Python26\lib\site-packages\django-1.1.2-py2.6.egg\django\core\management\base.py", line 222, in execute
    output = self.handle(*args, **options)
  File "C:\Python26\lib\site-packages\south-0.7.1-py2.6.egg\south\management\commands\migrate.py", line 81, in handle
    apps = [Migrations(app)]
  File "C:\Python26\lib\site-packages\south-0.7.1-py2.6.egg\south\migration\base.py", line 60, in __call__
    self.instances[app_label] = super(MigrationsMetaclass, self).__call__(app_label_to_app_module(app_label), **kwds)
  File "C:\Python26\lib\site-packages\south-0.7.1-py2.6.egg\south\migration\utils.py", line 41, in app_label_to_app_module
    app = models.get_app(app_label)
  File "C:\Python26\lib\site-packages\django-1.1.2-py2.6.egg\django\db\models\loading.py", line 139, in get_app
    raise ImproperlyConfigured, "App with label %s could not be found" % app_label
django.core.exceptions.ImproperlyConfigured: App with label forum could not be found