Most of the interaction takes place in a small window that looks like an IM window (of course you can expand it to whatever size you like). It contains several tabs let you switch between messaging a user, searching for users and reading archived messages.
It pops up (or to the front) whenever:
- you click on a name in the online users list
- you click on a link on any participants page
- you click on a general link in the participants block
- you have a new message sent to you (achieved by a bit of javascript inserted into any Moodle page from the header)
Users have preferences to
- allow the window to pop up or not
- allow their own comments to be logged
- choose a forwarding destination (email, Jabber, other IM etc)
- choose a forwarding preference
- forward messages always
- forward messages only when "away"
- forward messages never
If two users are on at the same time:
- the messaging window (tab) looks like a private chat
- others can be invited to the little chat
The extent to which this can be integrated with the chat code has not been determined yet.