REPLACE THE FOLLOWING CODE AT LINE 456 of db-lib.pl in the Library
directory (flatfile_apply_criteria subroutine):

=============================================================
      if ($c_type =~ /date/i)
        {
        ($month, $day, $year) = split(/\//, $db_value);

        $month = "0" . $month
          if (length($month) < 2);

        $day = "0" . $day
          if (length($day) < 2);

        $year = ($current_century-1) . $year
          if (length($day) < 3);
 
                # Then we will assign the new formatted date to $db_date.

        $db_date = $year . $month . $day;

                # Next, we will perform the same type of reformatting on
                # the user-submitted date that we did for the date in the
                # database.

        ($month, $day, $year) = split(/\//, $form_value); 

        $month = "0" . $month
          if (length($month) < 2);

        $day = "0" . $day
          if (length($day) < 2);
                
        $year = ($current_century-1) . $year
          if (length($day) < 3);
                
                # The user-submitted formatted date is stored in
                # $form_date   
                
        $form_date = $year . $month . $day;
=============================================================
WITH THE FOLLOWING CODE:
=============================================================
      if ($c_type =~ /date/i)
        {
        ($month, $day, $year) =
          split(/\//, $db_value);
        $month = "0" . $month
          if (length($month) < 2);
        $day = "0" . $day
          if (length($day) < 2);
        if ($year > 50 && $year < 1900) {
          $year += 1900;
        }
        if ($year < 1900) {
          $year += 2000;
        }
        $db_date = $year . $month . $day;

        ($month, $day, $year) =
          split(/\//, $form_value);
        $month = "0" . $month
          if (length($month) < 2);
        $day = "0" . $day
          if (length($day) < 2);
        if ($year > 50 && $year < 1900) {
          $year += 1900;
        }
        if ($year < 1900) {
          $year += 2000;
        }
        $form_date = $year . $month . $day;
=============================================================