Why isn't the jQuery script file being recognized in the Django admin panel?

Question

I'm following Django's provided tutorial, but I've now discovered that jQuery isn't being loaded, so collapsible fieldsets in the administration panel do not work. This was because libjs-jquery wasn't yet installed on the system, but installing did not fix the problem.

Page not found (404)
Request Method: GET
Request URL:    http://mysite:8000/static/admin/js/jquery.js

I've confirmed that /usr/share/pyshared/django/contrib/admin/media/js/jquery.js points to the correct file (/usr/share/javascript/jquery/jquery.js) and that the aforementioned /usr/.../js/ directory is where mysite:8000/static/admin/js/ reads from. I've also noticed that creating a new file in that /usr/.../js/ folder does not make it appear on the site itself. My best guess is that Django does not recheck the filesystem unless told to do so. Does anyone know how I should fix this problem?