You need RepairPrivileges Utility from Apple.
From Apple Knowledge Base (under Support tab of Apple.com):
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TITLE
Mac OS X: About the Repair Privileges Utility 1.1
Article ID:
Created:
Modified: 106900
6/11/02
7/17/02
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TOPIC
The Repair Privileges utility restores the privileges (or "permissions") of Mac OS X system files and Apple-installed software to their default configuration. This document contains a link for downloading the Repair Privileges utility.
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DISCUSSION
Repair Privileges Utility
Download Requirements
Operating System
Mac OS X 10.1.5 only