Wiki capabilities on a custom post type

I'm using CustomPress and have defined new post_types. I'd like to add a capability to have the "talk" (or "discuss") tab as in a Wiki on my custom post_type posts. I'm interested in letting registered users add posts from the frontend (I planned to use WP Frontend Pro plugin for that), and I want to allow the Talk/History functions a Wiki provides. Is it possible with you "Wiki" plugin? If not, are you aware of any plugin available for this? Thanks.