On Windows, compile like this : javac -classpath pircbot.jar;rssutils.jar;. *.java run like this java -classpath pircbot.jar;rssutils.jar;. Joe6botMain if you want to specify the nick name run like this java -classpath pircbot.jar;rssutils.jar;. Joe6botMain Nick
On any sane OS, replace those ; with : and you are good to go