Forum .LRN Q&A: Response to Message View in Forums is very slow on Postgresql

I suspect the function calls in this query are the culprit:

 select forums_messages.*,
                   person__name(forums_messages.user_id) as user_name,
                   party__email(forums_messages.user_id) as user_email,
                   forums_forum__name(forums_messages.forum_id) as forum_name,
                   forums_message__root_message_id(forums_messages.message_id) 
as root_message_id,
                   (select fm2.subject
                    from forums_messages fm2
                    where fm2.message_id = forums_message__root_message_id(foru
ms_messages.message_id)) as root_subject,
                   to_char(forums_messages.posting_date, 'Mon DD YYYY HH24:MI:S
S') as posting_date
            from forums_messages
            where forums_messages.message_id= :message_id

This is in the proc forum::message::get, the select_message query.