Domain casting still not working right?

This particular case arose during work on the information schema:

-- good

select cast(55::oid AS varchar);
varchar
---------
55
(1 row)

-- bad

create domain test as varchar;
CREATE DOMAIN
select cast(55::oid AS test);
ERROR: Cannot cast type oid to test

--
Peter Eisentraut peter_e(at)gmx(dot)net