A user equipment (UE) transmits a first START value to a serving radio network controller (RNC), and utilizes the first START value as a most-recently transmitted START value. A serving radio network subsystem (SRNS) relocation procedure is then initiated between the UE, the serving RNC and a target RNC. In response to the SRNS relocation procedure, the serving RNC transmits a SRNS relocation information container to the target RNC. The SRNS relocation information container includes the START value of each CN domain and the Latest configured core network (CN) domain. The target RNC utilizes the START value of the Latest configured CN domain to initialize the hyper-frame numbers (HFNs) of radio bearer RB2. The UE re-establishes RB2 and utilizes the first START value to initialize the HFNs of RB2. The UE then transmits a response message to the target RNC on RB2.