A mobile IPv6 dual-stack node engages in IPv6 communication while roaming within an IPv4-only network, for example using ISATAP. First, the node determines that it has moved Bnd obtains a new IPv4 address. After determining that the visited network contains no IPv6-enabled components, the node uses an IPv6 connect agent to engage in IPv6 communication. The node configures its care-of address using the IPv6 connect agent's routing information and the node's newly-obtained IPv4 address. In one embodiment, the node and the connect agent optimize the handoff when the nodes has moved but still uses the same connect agent. The node sends a binding updates to the connect agents comprising the node's old care-of address and the node's new care-of address. When the connect agent receives a packet destined for the node's previous care-of address, it forwards the packet to the node's currents care-of address, thereby reducing packet loss.