In an embodiment, a user equipment (UE) determines that a current serving network is associated with a network support zone of a given type, wherein network support zones of different types are characterized by different levels of support for a multimedia client application configured to manage server-arbitrated communication sessions at the UE. The UE loads zone-specific network procedures for supporting the multimedia client application within the network support zone of the given type, and then executes the zone-specific network procedures at the UE. In another embodiment, an application server determines that the current serving network of the UE is associated with the network support zone of the given type. The application server selects zone-specific network parameters and/or features based on the determination, and then interacts with the multimedia client application within the network support zone of the given type with the selected zone-specific network parameters and/or features.