dbms_job

Hello list,
I am running 9.2.0.1.0 enterprise edition on win32. Why doesn't the "Supplied PLSQL Packages and Types Reference" docs mention dbms_system ?
It doesn't seem to be explained anywhere in the docs although the admin docs say that it can be used enable sql_trace for another session. I was able to do that only after learning about its parameters thru : sql> describe dbms_system
while I was logged in as sysdba.

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