Looking through the source for https://trac.bbpress.org/browser/trunk/bb-includes/db-mysqli.php I don’t see the provision for setting a port number (someone correct me if it is actually accounted for somewhere else.)
MySQL normally operates on port 3306, not 1337, so I don’t know if you are making up that port or if your host actually runs MySQL on that port. If he does run MySQL on that port, then I don’t know what to do.
If it’s actually port 3306, everything will work fine if you set this in config.php:
define('BBDB_HOST', 'blabla.bla.pl'); with no http and no colon and no port.