Installation instructions and other details are on the project page:
http://www.fijiwebdesign.com/products/openfire-joomla-integration-plugin.html


1) Where do I get the Joomla OpenFire Plugin.

You will need to visit the project page.
http://www.fijiwebdesign.com/products/openfire-joomla-integration-plugin.html

2) What do I need to use the Joomla OpenFire plugin?

You need to have a working version of the OpenFire Instant Messaging Server (XMPP/Jabber Server). You also need to have a working version of the Joomla Content Management System (CMS) of version 1.5 or higher.
You need to be able to edit the OpenFire server configuration file. This is an XML file found at: openfire/config/openfire.xml where openfire is the installation directory of the OpenFire sever.

3) What does it achieve?

It allows your Joomla users to have OpenFire accounts. This allows them to log into your IM server using their Joomla username and your domain name. eg: This e-mail address is being protected from spam bots, you need JavaScript enabled to view it  

4) How does it work?

When a user tries to log into their IM account on your OpenFire server, OpenFire will query the Joomla database for the username and password of that user. If successful, OpenFire will log them into the sever under their Joomla username.

In the background, the Joomla OpenFire plugin will update the username and password of users when ever they log into Joomla, making them available to OpenFire when they need to log into the IM sever.

We are also developing functionality to use the http user management plugin for Openfire that allows Joomla to update OpenFire accounts over HTTP.
http://www.igniterealtime.org/projects/openfire/plugins/userservice/readme.html

This is for users that cannot access their database across domains.