Following functions return NOT_SUPPORTED status

javacall_serial_set_dte_signal(javacall_handle handle, javacall_serial_signal_type signal, javacall_bool value);
javacall_result /*OPTIONAL*/
javacall_serial_get_dce_signal(javacall_handle handle, javacall_serial_signal_type signal, javacall_bool* value);
javacall_result /*OPTIONAL*/
javacall_serial_start_dce_signal_listening(javacall_handle handle, javacall_handle owner, javacall_handle* context);
javacall_result /*OPTIONAL*/
javacall_serial_stop_dce_signal_listening(javacall_handle context);