A new webchat client was rolled out on redbrick in September 2009.
It is based upon qwebirc which is an AJAX IRC client and is the default webchat client on quakenet.
How to Login
Visit Redbrick WebChat.
You will be prompted to login to IRC with your Redbrick Username and Password using pubcookie. Enter your username and password.
Once you are logged in click "Connect".
Webchat should load and automatically join you into #lobby.
Most of the commands Webchat uses are the same as the other IRC clients on redbrick.
For examples of some of these commands see the article on IRC.
Connecting to channels automatically
By default you will automatically join #lobby.
If you wish to override this functionality once you have logged in with pubcookie remove &channels=lobby from the end of the url and reload the page.
You will now be prompted for your nickname and the channels you wish to join.
If you want to join multiple channels the list should be comma separated. (eg. #lobby,#intersocs,#bots,...).
This will only take effect for the current session and will have to be repeated each time you use webchat.