"SP2c to Resolve Shortage of Windows XP Product Keys
Due to the longevity of Windows XP Professional, it has become necessary to produce more product keys for system builders in order to support the continued availability of Windows XP Professional through the scheduled system builder channel end-of-life (EOL) date of January 31, 2009.

Timeline and Versions for SP2c Release
SP2c will be released into the System Builder channel in September to provide system builders with a new, extended range of product keys that will ship with:

Windows XP Professional (except for Simplified Chinese, Russian and Korean languages)
Windows XP Professional N
This release does not impact the following versions:
Microsoft Windows XP Home Edition
Microsoft Windows XP Media Center Edition
Microsoft Windows XP Tablet PC Edition
Microsoft Windows XP Professional 64-bit Edition

SP2c Features and Requirements
There are no other features or fixes included in this service pack; it will only allow for the inclusion of additional product keys. When using SP2c product keys, system builders must:

- Use the product keys with SP2c media.
- Create new images from SP2c to accommodate the new product keys. A hotfix will not be provided.

See Windows Life-Cycle Web site for more information on Microsoft’s support policy."