A system for outputting speech from speech data that may include an application, an internal speech data module, and an external speech data module is provided. The internal speech module stores default speech data that defines which speech data is compatible with the application. The external speech module, which may include a data carrier, may provide optional speech data, including a sequence identifier, separately from the application. To determine whether optional speech data fits the application, the application generates a sequence of one or more segment designators designating speech segments, and associating with them a sequence identifier. The application may also compare the sequence identifier generated by the application with that of the optional speech data. If a predetermined result occurs, the optional speech data may be used. Otherwise, the default speech data may be used. This method may be used to update default speech data with optional speech data.