userIsStaff ZPT error on login

Upon attempting to log in (both as admin and affiliate), I get the following error message:

URL: http://localhost:6543/communities
Module paste.evalexception.middleware:306 in respond
<< try:
                __traceback_supplement__ = errormiddleware.Supplement, self, environ
                app_iter = self.application(environ, detect_start_response)
                try:
                    return_iter = list(app_iter)>> app_iter = self.application(environ, detect_start_response)
Module repoze.zodbconn.middleware:14 in __call__
<<
        def __call__(self, environ, start_response):
            result = self.application(environ, start_response)
            if self.key in environ:
                del environ[self.key]>> result = self.application(environ, start_response)
Module karl.timeit:40 in __call__
<<
            # Generate the response. If text/html, print elapsed
            resp = req.get_response(self.app)
            if resp.content_type == "text/html":
                elapsed = str(1 / (time.time() - start))[0:5]>> resp = req.get_response(self.app)
Module webob:1325 in get_response
<< else:
                status, headers, app_iter = self.call_application(
                    application, catch_exc_info=False)
            return self.ResponseClass(
                status=status, headerlist=headers, app_iter=app_iter,>> application, catch_exc_info=False)
Module webob:1293 in call_application
<< captured[:] = [status, headers, exc_info]
                return output.append
            app_iter = application(self.environ, start_response)
            if (not captured
                or output):>> app_iter = application(self.environ, start_response)
Module repoze.errorlog:85 in __call__
<< environ['repoze.errorlog.entryid'] = identifier
                try:
                    return self.application(environ, start_response)
                except self.ignored_exceptions:
                    # just reraise an ignored exception
    >> return self.application(environ, start_response)
Module repoze.tm:19 in __call__
<< return start_response(status, headers, exc_info)
            try:
                result = self.application(environ, save_status_and_headers)
            except:
                self.abort()>> result = self.application(environ, save_status_and_headers)
Module paste.registry:350 in __call__
<<
            try:
                app_iter = self.application(environ, start_response)
            except Exception, e:
                # Regardless of if the content is an iterable, generator, list
    >> app_iter = self.application(environ, start_response)
Module repoze.who.middleware:107 in __call__
<<
            wrapper = StartResponseWrapper(start_response)
            app_iter = app(environ, wrapper.wrap_start_response)

            if self.challenge_decider(environ, wrapper.status, wrapper.headers):>> app_iter = app(environ, wrapper.wrap_start_response)
Module tw.core.middleware:36 in __call__
<<
        def __call__(self, environ, start_response):
            return self.wsgi_app(environ, start_response)

        def wsgi_app(self, environ, start_response):>> return self.wsgi_app(environ, start_response)
Module tw.core.middleware:59 in wsgi_app
<< else:
                    # Pass request downstream
                    resp = req.get_response(self.application)
                return resp(environ, start_response)
            finally:>> resp = req.get_response(self.application)
Module webob:1325 in get_response
<< else:
                status, headers, app_iter = self.call_application(
                    application, catch_exc_info=False)
            return self.ResponseClass(
                status=status, headerlist=headers, app_iter=app_iter,>> application, catch_exc_info=False)
Module webob:1293 in call_application
<< captured[:] = [status, headers, exc_info]
                return output.append
            app_iter = application(self.environ, start_response)
            if (not captured
                or output):>> app_iter = application(self.environ, start_response)
Module tw.core.resource_injector:67 in _injector
<< def _injector(environ, start_response):
            req = Request(environ)
            resp = req.get_response(app)
            content_type = resp.headers.get('Content-Type','text/plain').lower()
            if 'html' in content_type:>> resp = req.get_response(app)
Module webob:1325 in get_response
<< else:
                status, headers, app_iter = self.call_application(
                    application, catch_exc_info=False)
            return self.ResponseClass(
                status=status, headerlist=headers, app_iter=app_iter,>> application, catch_exc_info=False)
Module webob:1293 in call_application
<< captured[:] = [status, headers, exc_info]
                return output.append
            app_iter = application(self.environ, start_response)
            if (not captured
                or output):>> app_iter = application(self.environ, start_response)
Module repoze.browserid.middleware:89 in __call__
<< # cookie hasn't been tampered with
                    environ['repoze.browserid'] = browser_id
                    return self.app(environ, start_response)

            # no browser id cookie or cookie value was tampered with
    >> return self.app(environ, start_response)
Module repoze.bfg.router:153 in __call__
<<
                response = registry.queryMultiAdapter(
                    (context, request), IView, name=view_name)

                if response is None:>> (context, request), IView, name=view_name)
Module zope.component.registry:217 in queryMultiAdapter
<< def queryMultiAdapter(self, objects, interface, name=u'', default=None):
            return self.adapters.queryMultiAdapter(
                objects, interface, name, default)

        def getMultiAdapter(self, objects, interface, name=u''):>> objects, interface, name, default)
Module zope.interface.adapter:482 in queryMultiAdapter
<< return default

            result = factory(*objects)
            if result is None:
                return default>> result = factory(*objects)
Module karl.views.communities:104 in show_communities_view
<< )

    def get_my_communities(communities_folder, request):
        # sorted by title
        principals = effective_principals(request)>> def get_my_communities(communities_folder, request):
Module repoze.bfg.chameleon_zpt:75 in render_template_to_response
<< renderer = renderer_from_cache(path, ZPTTemplateRenderer,
                                      auto_reload=auto_reload)
        result = renderer(**kw)
        response_factory = queryUtility(IResponseFactory, default=Response)
        return response_factory(result)>> result = renderer(**kw)
Module repoze.bfg.chameleon_zpt:29 in __call__
<<
        def __call__(self, **kw):
            return self.template(**kw)

    ZPTTemplateFactory = ZPTTemplateRenderer>> return self.template(**kw)
Module chameleon.core.template:42 in __call__
<<
        def __call__(self, **kwargs):
            return self.render(**kwargs)

        def write(self, body):>> return self.render(**kwargs)
Module chameleon.core.template:219 in render
<< def render(self, **kwargs):
            kwargs[config.SYMBOLS.xincludes] = self.xincludes
            return super(TemplateFile, self).render(**kwargs)

        def mtime(self):>> return super(TemplateFile, self).render(**kwargs)
Module chameleon.core.template:111 in render
<< def render(self, **kwargs):
            template = self.cook_check(parameters=kwargs)
            return self.render_template(template, **kwargs)

        def render_macro(self, macro, global_scope=False, parameters={}):>> return self.render_template(template, **kwargs)

(<PageTemplateFile /home/will/osi/karl3/src/karl/karl/views/templates/communities.pt>,)

Module chameleon.core.template:124 in render_template
<< __traceback_info__ = (self,)
            if config.DEBUG_MODE is False:
                return __template__.render(**kwargs)

            try:>> return __template__.render(**kwargs)
Module chameleon.core.translation:153 in render
Module chameleon.core.template:263 in render
<< def render(**kwargs):
                kwargs.update(self.bound_parameters)
                return self.render(name, parameters=kwargs)
            return Macro(render)>> return self.render(name, parameters=kwargs)
Module chameleon.core.template:116 in render_macro
<< template = self.cook_check(
                parameters=parameters, macro=macro, global_scope=global_scope)
            return self.render_template(template, **parameters)

        def render_xinclude(self, **kwargs):>> return self.render_template(template, **parameters)

(<PageTemplateFile /home/will/osi/karl3/src/karl/karl/views/templates/generic_layout.pt>,)

Module chameleon.core.template:124 in render_template
<< __traceback_info__ = (self,)
            if config.DEBUG_MODE is False:
                return __template__.render(**kwargs)

            try:>> return __template__.render(**kwargs)
Module ?:369 in render
Module chameleon.core.codegen:29 in lookup_attr
<< except AttributeError, e:
            try:
                return obj[key]
            except (KeyError, TypeError, AttributeError):
                raise e>> return obj[key]
Module karl.views.api:77 in __getitem__
<<
        def has_staff_acl(self, context):
            return getattr(context, 'security_state', 'inherits') == 'public'

        @property>> return getattr(context, 'security_state', 'inherits') == 'public'
ValueError: ZPT attempted to fetch userIsStaff