When you save the DTS package you can specify an owner password. If you do this, even sysadmins won't be able to modify the package without it, but anyone who knows the password will be able to make changes.
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If most people are not willing to see the difficulty, this is mainly because, consciously or unconsciously, they assume that it will be they who will settle these questions for the others, and because they are convinced of their own capacity to do this. -Friedrich August von Hayek
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