You don't ever need compass on your production servers, but you do need it on any development or build servers (anywhere you're going to compile the css).
This compass command:
compass compile --force -e production path/to/project
can be called from any shell script or the executed from another program as long as compass is on the PATH.
You might need to patch django-css to teach it about compass if it doesn't know about it yet.
Another approach is to pass the following options to the sass CLI. this still requires compass to be installed but might be able to work with django-css out of the box:
-r compass `compass imports`