wrong db_select in fbconnect_invite.module

db_select at line 202 causes fatal error:

      if ($fbid) {
        $res = db_select('fbconnect_users', 'f')
          ->fields('f', 'uid')
          ->condition('fbuid', implode($fbid, ','), 'IN')
          ->execute();

error:

Argument 2 passed to SelectQuery::fields() must be an array, string given, called in /var/aegir/platforms/drupal-7.7/sites/all/modules/fbconnect/fbconnect_invite/fbconnect_invite.module on line 203 and defined in SelectQuery->fields()