Method for accessing extended capabilities in mobile communication device using a subscriber identity module

Abstract

A mobile communication device (102) capable of performing non-standard communication modes, such as dispatch calling uses a subscriber identity module (SIM) (104). In order to allow the use of the non-standard, or extended features, the SIM has information for allowing use of the extended features stored therein (112). In order to determine if the SIM in the mobile communication device allows extended feature, the SIM must be checked upon initialization (202) of the mobile communication device. The mobile communication device has, stored in a non-volatile memory, a directory name or address of a feature directory in the SIM (111), and a copy of a feature signature file (111). The mobile communication device first checks to see if the directory is present (206) having the name stored in the mobile communication device, or at the address provided in the mobile communication device. If a directory exits, the mobile communication device looks for the feature signature file (210) and compares it to the copy stored in the mobile communication device (212). If the feature signature file matches, the extended features are enabled (214), and usable by the user of the mobile communication device.

Dependencies are inferred from the claim text.