The present invention provides apparatuses, methods, computer programs, computer program products and computer-readable media regarding IMS (Internet Protocol Multimedia Subsystem) restoration support for temporary GRUU (Globally Routable User Agent Uniform Resource Identifier). Certain aspects of the present invention include creating, at a registrar, a registration identified by a registration identifier, and storing, by the registrar, the registration identifier, a call identifier and an initial command sequence related to the registration identified by the registration identifier in a persistent database during the registration.