For Everyone Having Trouble with Mibbit
There is a Java applet that will be able to connect you to the channel, but you must follow the following steps:
1) Go to http://pjirc.com/demo.php
2) Enter a nick, and select "Normal" for Applet Style (unless you want to try a different client mode. I haven't.)
3) Click Chat!. You'll end up at the main irc server of pjirc. Not to worry, you can still get to irc.jayisgames.com.
4) Type in /server irc.jayisgames.com
5) Then, type in /join #quadradius
6) Boom! You're there.
If you need to change your nick, the command is /nick [username]
Changed for the sake of mobile browsers everywhere.