MS Article ID: 971620
During the installation of the 2007 Microsoft Office servers Service Pack 2, a product expiration date is activated incorrectly. This means that the product will expire 180 days after Service Pack 2 is deployed, as if it were a trial installation.
If you have applied the manual fix then this does not concern you. If have not and or are planning SP2 upgrade, then the recommended solution is to apply the following updates available from the Microsoft Download Centre:
Note: for background, refer to previous post regarding this.