If the file cannot be decoded and the date/time looks wrong, the file may have been generated using a version where some of the desciptors were placed on byte boundaries.  This was done to speed up the encoding process.  It only affects these particular desciptors:

004002MONTH                                   MONTH                       0        0    8
004003DAY                                     DAY                         0        0    8
004004HOUR                                    HOUR                        0        0    8
004005MINUTE                                  MINUTE                      0        0    8
004006SECOND                                  SECOND                      0        0    8
004043DAY OF THE YEAR                         DAY                         0        0   16
005002LATITUDE(COARSE ACCURACY)               DEGREES                     2    -9000   16
005003ALTERNATE LATITUDE                      DEGREES                     2    -9000   16