Prohibiting users from changing their password?

        This topic may have been discussed recently, but I have been unable to find any information in the archives.

        I'm interested in the ability to prohibit users from altering their own passwords. We have a distributed environment and would like to maintain the same ID/Password pair on each instance. We've implemented the tools to perform global updates at each instance. But, we still don't know how to prevent users from altering their own account passwords on a single instance.

        I've tried placing a trigger on the underlying SYS user table, but triggers are not allowed on SYS objects. Modifying the USER_PROFILE table didn't work real well either because it only allows you to prevent users from executing the "ALTER" command. This way a user can not alter their password, but they also can not alter any objects (tables, indexes).

        Our environment is Sun servers with 7.0.12.

        Does anybody have any suggestions?

        Thanks,

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