A protocol proxy relationship is established between a non-enabled host and a protocol-enabled router or other node in a multimedia session including a mobile communications network. A mechanism is provided that allows a non-enabled mobile terminal to communicate a protocol proxy request with a protocol-enabled node along an end-to-end path between the mobile terminal and a remote host. A mechanism is further provided to install information in the protocol enabled node so that it can function as the protocol proxy for the non-enabled mobile terminal.