Drools, jBpm and Guvnor are moving from codehaus irc servers to freenode. You can now find us on the following channels on irc://chat.freenode.net
#drools
#droolsdev
#jbpm
#jbpmdev
#guvnor
#guvnordev

freenode also maintains a web interface:
http://webchat.freenode.net/