The present invention relates to a session handling entity and an application server (AS) in a communication system, the session handling entity (S-CSCF) is obtaining, from a register entity, a correlation identity for a registering private user identity of a user, transmitting the correlation identity as part of a registration procedure to the application server, and the application server initiates, based on a received session request associated with the user, at least one session request towards corresponding number of devices of the user wherein the application server is configured to check the correlation identity to ensure that not more than one session request is initiated for each device of the user.