Here is a follow-up for anyone else having this problem. I had this problem and noticed some similarities between my situation and David's. This doesn't seem to be user error, but rather a mini perfect storm that comes together to cause the problem:
First I was using an object_identifier. This is a field in the web.config that you can specify as a string to prefix all database objects. Most people don't use this feature.
Second I had changed hosts and in doing so changed the username of my database during migration to the new host. For some reason every object in my database changed owner names properly except for two stored procedures: Forum_NewsArticleAdd and Forum_UserThreadsDelete. I am guessing that some sort of permissions issue caused this.
The solution was to alter the owner using this script and to delete the second stored proc because for some reason it existed twice under the old database owner and the new database owner. If you'r having this problem then consider doing the same.
As always backup your DB and file system before going forward. USE at YOUR OWN RISK.
**Note that the _jou in the script below was my objct identifier so replace that with your own.
alter schema [New_Owner_Name] transfer [Old_Owner_Name]._jou_Forum_NewsArticleAdd
alter authorization on [New_Owner_Name]._jou_Forum_NewsArticleAdd to schema owner
delete [Old_Owner_Name]._jou_Forum_UserThreadsDelete