# File ./session.rb, line 570
    def register_roster_filter
      @connection.add_filter("rosterFilter") do |element|
        if element.element_tag=="iq" and element.query.attr_xmlns=="jabber:iq:roster" and element.attr_type=="set"
          element.consume_element
          item = element.query.item
          if item.attr_subscription=="remove" then
            @roster.remove(item.attr_jid)
          else
            @roster.add(item.attr_jid, item.attr_subscription, item.attr_name, item.group.element_data)
          end
        end
      end
    end