ORA-00031

A windows95 pc hangs while executing forms. Then, his session remains active forever. I query v$sqltext to see whats being done by this session, and it's doing only any simple select statement.
I olso query the v$lock to check that there is no locking involved with this session.
I alter system kill session, and I receive this error: ORA-00031 Session marked for kill, which means that the session is involved in a non-interruptible operation. I've waited during days, but this session will not die.

How can I find out what kind of "non-interruptible operation" is this session involved in?

Thanks.

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Julio César Glez Suarez
Xixón, Asturies, Spain
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