Django RSS feed 500 error

I'm working on setting up an RSS feed for my Django-based blog. I'm getting 500 errors when I try and access the URL:

$ curl -I http://172.16.91.140:8000/blogg/feeds/latest/HTTP/1.0 500 INTERNAL SERVER ERROR

WSGIServer is reporting nothing more than

[25/Aug/2011 20:21:41] "HEAD /blogg/feeds/latest/ HTTP/1.1" 500 0

Under blogg/ I've got two files:

feeds.py:

from django.contrib.syndication.feeds import Feedfrom blog.models import *class BlogFeed(Feed):    title = "Test Title"    link = "/sitenews/"    description = "Test Description"    def items(self):        return Blog.objects.filter( is_published = True ).order_by('-id')[:10]    def item_title(self, item):        return item.subject    def item_description(self, item):        return item.subject    def item_pubdate(self,item):        return item.blog_time

and urls.py

from django.conf.urls.defaults import patterns, include, urlfrom blog.feeds import *feeds = {'latest': feeds.BlogFeed,}urlpatterns = patterns('blog.views',    (r'^$', 'index'),    (r'^(?P<blog_id>\d+)/$', 'detail'),    (r'^past-bloggs/', 'country_listing'),    (r'^past-bloggs/(?P<country_name>\w+)/$', 'city_listing'),    )urlpatterns += patterns('',    url(r'^feeds/(?P<url>.*)/$', 'django.contrib.syndication.views.feed', {'feed_dict': feeds}, name='feeds'),)

Any idea where I could be going wrong? Thanks guys.