Add Employee ID Attribute (DSforum2wiki)

Before you move into production, test it. Take a valid backup in production before proceeding with the change. 

You will find lots of information into the below link for schema modification.

http://social.technet.microsoft.com/Forums/en-US/winserverDS/thread/8aed0f64-8082-4414-98d4-c7968eaf4b72

Other Articles:

If you must edit the schema editing, but edit to anything... (Editing the scheme and creating a Display-Specifier)

http://adisfun.blogspot.com/2009/05/add-employee-id-field-aduc.html

http://pberblog.com/post/2009/06/21/Add-extra-columns-to-Active-Directory-Users-and-Computers-display.aspx

http://msexchangegeek.com/2010/05/06/how-to-add-employee-numbers-in-aduc-and-exchange-gal/

Shows how the Active Directory Users and Computers console and Employee id?

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