The present invention concerns a gateway device and a method at the gateway, the gateway device comprising an interface to a residential phone wiring comprising more than one plugging means for connecting at least one analogue phone, a broadband interface to a network comprising a central office, the central office being adapted to provide a first voice service type to the at least one analog phone, an FXS module for providing a voice over IP service over the broadband interface to the at least one analogue phone when the first voice service type is disabled, unbundling detection means for detecting the presence of the first voice service type, connecting the FXS module to the residential phone wiring when the first voice service type is disabled, and disconnecting the FXS module from the residential phone wiring when the first voice service type is enabled, and a management agent for informing a gateway management server when changing from the first voice service type to the voice over IP service and vice versa, so that the same phone number can be used when using the first voice service type or the voice over IP service.