An integrated circuit for controlling a user equipment, the integrated circuit comprising: receiving circuitry, which is configured to receive a minimum-system-information message from a first radio base station controlling a first radio cell of a mobile communication system, wherein system information for the first radio cell that can be acquired by the user equipment is carried within the minimum-system-information message and one or more additional-system-information messages, the minimum-system-information message including system information for accessing the first radio cell and including at least one system information index, each system information index being associated with one of the additional-system-information messages, wherein the system information index comprises a value tag and an area pointer, the area pointer pointing to one area already defined, processing circuitry, which is configured to determine whether the user equipment had already acquired before the additional-system-information message being associated with the same value tag and the same area as indicated by the system information index received in the minimum-system-information message, and if the determination is positive, the processing circuitry is configured to determine that system information included in said additional-system-information message acquired before is applicable to the first radio cell, wherein an area type list is stored in the user equipment, wherein each item in the area type list is associated with a list number and an area type, wherein the area pointer indicates a list number of the area type list, wherein the processing circuitry is configured to determine the area type based on the area pointer and the area type list and to determine an area identification based on the determined area type and a previously acquired area identification for said determined area type, wherein the processing circuitry is configured to determine whether the additional-system-information message acquired before is applicable for the same area based on the determined area type and determined area identification. receiving circuitry, which is configured to receive a minimum-system-information message from a first radio base station controlling a first radio cell of a mobile communication system, wherein system information for the first radio cell that can be acquired by the user equipment is carried within the minimum-system-information message and one or more additional-system-information messages, the minimum-system-information message including system information for accessing the first radio cell and including at least one system information index, each system information index being associated with one of the additional-system-information messages, wherein the system information index comprises a value tag and an area pointer, the area pointer pointing to one area already defined, processing circuitry, which is configured to determine whether the user equipment had already acquired before the additional-system-information message being associated with the same value tag and the same area as indicated by the system information index received in the minimum-system-information message, and if the determination is positive, the processing circuitry is configured to determine that system information included in said additional-system-information message acquired before is applicable to the first radio cell, wherein an area type list is stored in the user equipment, wherein each item in the area type list is associated with a list number and an area type, wherein the area pointer indicates a list number of the area type list, wherein the processing circuitry is configured to determine the area type based on the area pointer and the area type list and to determine an area identification based on the determined area type and a previously acquired area identification for said determined area type, wherein the processing circuitry is configured to determine whether the additional-system-information message acquired before is applicable for the same area based on the determined area type and determined area identification.