A method is provided of deactivating PDP Context upon transfer of a connection with a user terminal between a femtocell base station and a macrocell base station, the method comprising: the femto base station receiving a message including a first identifier of a PDP Context, altering the identifier of a PDP Context to a second identifier, and forwarding the altered message to the core network, the core network receiving a message including an identifier determines that the received identifier does not match the identifier that it expects and so deactivates the PDP Context.