Conference plugin or how to ... please help


I'm starting to build a social network for my company and they need a Conference module (not VideoConference). This conference module needs offline support so when a topic is posted invited users can leave post whenever they want to so there is not need for online support or chatting support. A conference is like a blog entry but with the main difference I need to add 3 options of publication: anonymous, partially anonymous and public. If conference owner or publisher pick anonymous then not usernames are showed never even for conference owner, if pick partially anonymous then usernames are showed for conference owner and if pick public then usernames are visible to everyone even to people invited to the post/topic. Any plugin do this? Any help?