def publish(data, message_title = nil)
      mode = :persistent_sequential
      if message_title
        mode = :persistent
      else
        message_title = "message"
      end
      @zk.create("#{full_queue_path}/#{message_title}", data, :mode => mode)
    rescue ZK::Exceptions::NodeExists
      return false
    end
def publish(data, message_title = nil)
      mode = :persistent_sequential
      if message_title
        mode = :persistent
      else
        message_title = "message"
      end
      @zk.create("#{full_queue_path}/#{message_title}", data, :mode => mode)
    rescue ZK::Exceptions::NodeExists
      return false
    end
@private
 :nodoc:
 publish a message to the queue, you can (optionally) use message titles
 to guarantee unique messages in the queue

 @param [String] data any arbitrary string value

 @param [String] message_title specify a unique message title for this
   message (optional)