How can I add another host to the proxy-list

Issue

This is the modcluster subsystem taken from the EAP's standalone-ha.xml
The question is: how can I add another host, for example host2:6666 to the proxy list ?

        <subsystem xmlns="urn:jboss:domain:modcluster:1.2">
            <mod-cluster-config advertise-socket="modcluster" advertise="false"
                 connector="ajp" proxy-list="host1:6666">
                <dynamic-load-provider>
                    <load-metric type="busyness"/>
                </dynamic-load-provider>
            </mod-cluster-config>
        </subsystem>