SQL Server 2005 does automatically audit the SQL Server Agent when you choose Log Audit and Existing Connection. You can monitor Broker also, but that is a specific choice. Not sure about SQL Server 2000, but I think it monitors SQL Server Agent automatically.
Also, not sure about the SA login, but I'd assume that's automatic too unless you choose to ignore system events.
Catadmin - MCDBA, MCSA
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