Clearspace can definitely utilize Wildfire as a resource for chat. In the admin console, use the "Real Time" tab to setup Clearspace as an external component to Wildfire. Currently the only feature that is enable is shared presence information. If setup correctly, you will be able to view a user''s presence (as well as any away messages) from their profile page. If the user is online, you will be able to start a chat from Clearspace by simply clicking on a link. The link is a simple xmpp:// link, so it will open whatever chat client you are using, ie Spark.
In the near future we plan to make real time integration with Wildfire a big component of Clearspace, including private and group web based chat, IM notifications (watches/rss), and real time document editing with a private author discussion.
Let us know if you have any questions getting Clearspace setup with Wildfire.
Thanks for the quick reply Nick. Great answer.