RMAN 11G Issue: ORA-20446 and ORA-06512

Ran into this one today when trying to setup a new tablespace backup via RMAN in a newly installed Oracle 11.1.0.7 instance on RedHat Linux:
ORA-20446: The owner of the job is not registered ORA-06512: at "SYSMAN.MGMT_JOBS", line 168 ORA-06512: at "SYSMAN.MGMT_JOBS", line 86 ORA-06512: at line 1

It turns out that this is a know bug with 11G. With a simple workaround:
Login as SYSMAN and execute the following command for the users in question:

EXECUTE MGMT_USER.MAKE_EM_USER(‘’);