How to check the status of the Automated Maintenance Tasks in Oracle 11g

To see the currently enabled jobs in your database, use the dictionary view DBA_AUTOTASK_OPERATION
which displays all automated maintenance task operations for each client:

select client_name,operation_name,status  
from DBA_AUTOTASK_OPERATION;

Example from one of my 11g databases:

CLIENT_NAME	OPERATION_NAME	STATUS
auto optimizer stats collection	auto optimizer stats job	DISABLED
auto space advisor	auto space advisor job	ENABLED
sql tuning advisor	automatic sql tuning task	DISABLED