Federal W4 Lock In Date

This is quoted from Oracle HRMS Help: 

The IRS can issue a notice rejecting the claim for more than 10 allowances, and indicating the number of allowances the employee can claim.  In the Allowance Reject Date field enter the date from the IRS notice, and reduce the number of allowances in the W-4 information region.

I found, on Metalink, the the 2006 YE1 patch changed the name from Allowance Reject Date to Lock In Date.  I went into a test environment, changed an employee's allowances to Single and Zero, saved, added a lock in date, saved again.  Then I date tracked forward a few months, deleted the lock in date, saved, changed the exemptions, saved again.