Looping tasks

Are there are Oracle users who have, or have had, problems with "looping" tasks? For example if a database user does not end his session cleanly then when the database is shutdown the user's task (still in a broken state on the system) suddenly starts looping? I've had advice about the use of "sig-hup" and "keep-alive", but we still have problems from time to time so I'm hoping for a "been there, done that, got the T-shirt" person who could offer some advice?

Jeremy Youngman             | ###### ## ## |          BUSINESS          |
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