How to trace what is happening inside the stored procedure

Hi:

I am running a stored procedure(say P1 with 5000 lines) using a particular session (say sid=135).

By joining gv$session and gv$sql, I can identify whether the stored procedure is running or not.
But is there a way to indentify, what is the current operation (within the stored procedure, what particular statement being executed) OR where we are in the stored procedure

Thanks in advance,

-- 
Sami Seerangan
Oracle DBA
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http://www.freelists.org/webpage/oracle-l