/span></dt>
        <dd>This property contains information about how the message was split from
        the original message. If passed to the <b>join</b> node, the sequence can be
        reassembled into a single message. The property has the following properties:
        <ul>
            <li><code>id</code> - an identifier for the group of messages</li>
            <li><code>index</code> - the position within the group</li>
            <li><code>count</code> - if known, the total number of messages in th