Anyone have auto DB shutdown script for NT?

Does anyone have a mechanism for automating the shutdown of Oracle databases on NT when someone shuts down the server? Preferably, I would like to have the capability of running a script(s) prior to server shutdown that would shutdown all databases that are currently active.

I have been unsuccessful in finding anyone who can suggest a method for doing this. We have no problem in starting up the databases at server startup, but if someone shuts down the server or reboots the server without manually shutting down the databases, we experience less than graceful shutdowns of the databases.

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