Patent ID: 8326289

Claim:
A method, comprising: communicating a first network location inquiry message from a first gateway, bridging a first wireless communication network to a second wireless communication network, to a first base station that belongs to the first wireless communication network, wherein the first network location inquiry message is destined for a first mobile station that has the first wireless communication network as its home wireless communication network; communicating a second network location inquiry message, different from the first network location inquiry message, from a second gateway, bridging the second wireless communication network to the first wireless communication network, to a second base station that belongs to the second wireless communication network, different from the first wireless communication network, wherein the second network location inquiry message is destined for the first mobile station that has the second wireless communication network as a possible visited wireless communication network; transmitting the first network location inquiry message from the first base station and the second network location inquiry message from the second base station to the first mobile station; communicating, in response to one of the first network location inquiry message and the second network location inquiry message, an acknowledgment message from the first mobile station to the gateway; determining, at the first gateway, that the first mobile station is registered with the first wireless communication network when the acknowledgment message is communicated to the first gateway via the first base station in response to the first network location inquiry message; and determining, at the second gateway, that the first mobile station is registered with the second wireless communication network when the acknowledgment message is communicated to the gateway via the second base station in response to the second network location inquiry message, and responsively: i) transmitting a notice from the second gateway to the first gateway informing the first gateway of a presence of the first mobile station in the second wireless communication network; and ii) responsive to receiving the notice, the first gateway providing a first virtual mobile station at the first gateway through which all incoming and outgoing calls with the first mobile station at its location in the second wireless communication network will be routed.