Django error in Heroku: "Please supply the ENGINE value"

I read and apply "Getting started with Django on Heroku" tutorial but ran into problem while syncing db:

raise ImproperlyConfigured("settings.DATABASES is improperly configured." 
django.core.exceptions.ImproperlyConfigured: 
settings.DATABASES is improperly configured. Please supply the ENGINE value. 

I read Please supply the ENGINE value Django database configuration and “settings.DATABASES is improperly configured” error performing syncdb with django 1.4 but still receive same error. While executing

heroku run python manage.py --settings=moz455.settings syncdb

I receive error "Unknown command: '--settings=moz455.settings'". How to solve this problem?

Version of Django is 1.4.