Since I lost the link already more than once I’ll use my blog as memory-extension 
In the NTDEV mailing list, there was lately a thread discussing problems of using a wrapper such as DDKBUILD around the build utility and compiler of the DDK/WDK. The problem surfaced with the WDK (Vista/Longhorn DDK) and VS 2005.
A blog entry at Microsoft’s MSDN blogs describes the same phenomenon. Of course there is no mentioning of the DDK/WDK 😉
// Oliver