From: John Cuccia 

On Sat, 11 Mar 2006 19:04:37 +1200, black.hole.4.spam{at}gmail.com (Don Hills) wrote:

>In article , "Gary Britt"
 wrote:
>>                  ...                            Maybe they want to
>>make sure big companies with in house techs don't do hardware upgrades
>>without buying new licenses of the next version of windows that they likely
>>didn't need or want.
>
>Big companies normally have site licenses. This allows them to do their own
>custom install images with their desired configuration and applications.
>This version also doesn't have the license key or reactivation
>requirement(*). There is one catch, in that each system on which this site
>license is used must also have a valid individual Windows license, either
>retail or preinstalled.
>
>(*) Windows 2000. I believe XP is the same but I'm open to correction.

Looks like you are correct:

http://www.microsoft.com/technet/prodtechnol/winxppro/evaluate/xpactiv.mspx
Product Activation and volume licenses Windows XP upgrade licenses acquired
through one of Microsoft's volume licensing agreements, such as Microsoft
Open License, Enterprise Agreement, or Select License, will not require
activation. Installations of Windows XP made using volume licensing media
and volume license product keys (VLKs) will have no activation, hardware
checking, or limitations on installation or imaging.

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