The Windows XP's product activation encryption algorithm has recently been "cracked", and a software implementation that emulates the telephone activation question / response procedure is available. This technically allows one to activate new XP installations, safely and securely, without a crack, offline even though Microsoft has turned off all the activation servers.
This is particularly relevant for those with older scientific equipment that relies on an XP computer. I think these would usually be sold with quite permissive licences, allowing one to change the computer freely and reinstall Windows XP. However it would appear that using this software could be "circumventing a technological measure or access control technology", and therefore illegal in the US.
Is this a reasonable interpretation of the law? Is there some exception that would apply in this case? Is there a way to utilise this application legally in such a situation?