PostgreSQL 9.2. CREATEROLE

[gmontee@localhost ~]$ psql -U postgres
psql (8.4.20, server 9.2.8)
WARNING: psql version 8.4, server version 9.2.
         Some psql features might not work.
Type "help" for help.

postgres=# CREATE ROLE rolecreator WITH LOGIN CREATEROLE;
CREATE ROLE
postgres=# \q
[gmontee@localhost ~]$ psql -U rolecreator postgres
psql (8.4.20, server 9.2.8)
WARNING: psql version 8.4, server version 9.2.
         Some psql features might not work.
Type "help" for help.

postgres=> CREATE ROLE superuser WITH LOGIN SUPERUSER;
ERROR:  must be superuser to create superusers