Postgres Error - Session pages - DATE_FORMAT

When browsing to www.example.com/program/session-schedule, the following error displays:

user warning: query: SELECT DISTINCT DATE_FORMAT(s.field_slot_datetime_value, '%Y-%m-%d') AS day FROM content_type_time_slot s INNER JOIN node n ON s.nid = n.nid AND s.vid = n.vid GROUP BY DATE_FORMAT(s.field_slot_datetime_value, '%Y-%m-%d') ORDER BY s.field_slot_datetime_value ASC in /var/vhost/drupal/cod-6.x-1.0-beta1/profiles/cod/modules/contrib/cod_support/cod_session/cod_session.module on line 867.

There are no sessions displayed, even if rooms/time slots are created, and sessions assigned.

The same error appears twice, and also appears here : www.example.com/program/session-schedule/your-schedule

I'm using Drupal 6.19 & Postgres 8.3.

I believe the error is caused because Postgres doesn't have a DATE_FORMAT function.

Having a look at views, this is how they got around it:

switch ($db_type) {
    case 'mysql':
    case 'mysqli':
      $replace = array(
        'Y' => '%Y',
        'm' => '%m',
        'd' => '%%d',
        'H' => '%H',
        'i' => '%i',
        's' => '%s',
        );
      $format = strtr($format, $replace);
      return "DATE_FORMAT($field, '$format')";
    case 'pgsql':
      $replace = array(
        'Y' => 'YYYY',
        'm' => 'MM',
        'd' => 'DD',
        'H' => 'HH24',
        'i' => 'MI',
        's' => 'SS',
        );
      $format = strtr($format, $replace);
      return "TO_CHAR($field, '$format')";
  }

Which is in the views_date_sql_format function.