The comment for the connect method says it does "connect/reconnect to a server". Reconnecting can be somewhat conveniently done by passing every parameter to it from the instance variables, but the ipv6 boolean is not stored. It would be nice if there were an ipv6 member for consistency, or even better a reconnect method that doesn't need all the arguments passed to it again.
Fixed in 46dfb06dffb6 and released as irc 0.8