All accounts, including trials, have unlimited conference room capabilities.
Using the Conference Rooms page in the admin dashboard, administrators can create rooms for staff. Any number of rooms can be created, and users can be flexibly assigned to rooms as desired.
Rooms are accessed through chat clients. The LibraryH3lp webclient provides a user's conference rooms automatically at the bottom of the main chat screen. Users in external XMPP clients such as Adium and Pidgin can also join these rooms using the credentials provided within the admin dashboard's Conference Rooms tab, in the External Client Access section for each room.
When an administrator assigns you to a conference room, you'll see that room appear in the bottom pane of the webclient after login. You can be assigned to more than one conference room; if so, you'll also see your list of available conference room. Each room shows a list of participants, the conference room transcript, and the room's current topic.
If you use an external client that supports XMPP multi-user chat to staff LibraryH3lp (both Pidgin and Adium do), your administrator can provide you with the credentials needed to access the room.
You can also create a multi-user conference room if you are using a client that supports them. However, rooms created via external XMPP clients will not be available to users in the webclient.
For those on the US server, conference room addresses look like firstname.lastname@example.org; regional servers are similar but will include the region as part of the domain like email@example.com for Europe. Just replace room-name with your actual room name. If your room does not already exist (i.e. you are creating a new room), then it will get auto-magically created. The person who creates the room becomes the owner. If that room already exists, you just join the conference.
More detailed info for Pidgin users:
There are a couple of ways to join or create rooms, but here is an easy way: