Why do taglists not show up in the question sidebar?

sidebar
question-page
askfedora
bug
retag add tags

I see that the admin interface has the option "Show tag list in sidebar" in the "Question page banners and sidebar"settings which is enabled by default. However, I don't see any taglists in the sidebar. This is the case for both askfedora staging and production instances. Unchecking the option results in an Internal Error. This is what the server log says:

[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88] mod_wsgi (pid=2147): Exception occurred processing WSGI script '/usr/sbin/askbot.wsgi'.
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88] Traceback (most recent call last):
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]   File "/usr/lib/python2.6/site-packages/django/core/handlers/wsgi.py", line 272, in __call__
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]     response = self.get_response(request)
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]   File "/usr/lib/python2.6/site-packages/django/core/handlers/base.py", line 169, in get_response
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]     response = self.handle_uncaught_exception(request, resolver, sys.exc_info())
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]   File "/usr/lib/python2.6/site-packages/django/core/handlers/base.py", line 218, in handle_uncaught_exception
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]     return callback(request, **param_dict)
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]   File "/usr/lib/python2.6/site-packages/django/utils/decorators.py", line 93, in _wrapped_view
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]     response = view_func(request, *args, **kwargs)
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]   File "/usr/lib/python2.6/site-packages/django/views/defaults.py", line 31, in server_error
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]     return http.HttpResponseServerError(t.render(Context({})))
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]   File "/usr/lib/python2.6/site-packages/coffin/template/__init__.py", line 54, in render
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]     return super(Template, self).render(**context)
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]   File "/usr/lib64/python2.6/site-packages/jinja2/environment.py", line 669, in render
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]     return self.environment.handle_exception(exc_info, True)
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]   File "/usr/lib/python2.6/site-packages/askbot/templates/500.html", line 1, in top-level template code
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]     {% extends "two_column_body.html" %}
[Tue Jun 04 11:32:22 2013] [error] [client 10.5.126.88]   File "/usr/lib/python2.6/site-packages/askbot/templates/two_column_body.html", line 1, in top-level template code ...

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