Moved the imports from the top of the file into the task function. This seemed to prevent some strange import errors that only occurred on the production server. I don't know if the problems were related to mod_wsgi or Python 2.5 or what.

Dear {{ to_name }},

Your friend, {{ sender_name }}, wanted to send you a link to an 
interesting story found on {{ site_name }}.

{{ story_title|safe }}
http://{{ site_url }}{{ story_link }}

Thanks!
http://{{ site_url}}