The MULTIMOB group has specified a base solution to support IP multicasting in a PMIPv6 domain [RFC6224]. In this document, an enhancement is proposed to the base solution to use a multicast tree mobility anchor as the topological anchor point for multicast traffic, while the MAG remains as an IGMP/MLD proxy. This enhancement provides benefits such as reducing multicast traffic replication and supporting different PMIPv6 deployments scenarios.