Accidentally Delete *.dbf Files, OH NO!!!

I have been working with Solaris for several years now. We have had a rare but particularly debilitating problem where certain people who will remain nameless, in an effort to "clean up" disk space, have nailed a .dbf file or two. I know I should have the solution to this on close at hand, but I seem to recall this was difficult, if not impossible, on other Unix platforms (such as AIX), because the file would be "locked" or "in use", and the nefarious "rm" command would fail. Alas, Solaris is all too willing to comply when asked.

Is there something that can be done, at the OS or Oracle level, to prevent such a thing? Needless to say, the "whackers" are using root to enter the command, so changing permissions would accomplish little. They are already set to only allow "oracle" write access.

Any help or even ridiculing chuckles and admonitions would be greatly appreciated.

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