[pwc] Building for kernel 2.6.20.11

[JCA]

   I have just tried to build the latest PWC driver against a
2.6.20.11 kernel, and the compilation does not get very far. What
happens is that the PWC code assumes the existence of a file called
config.h under include/linux in the kernel source tree - and that file
is absent from my 2.6.20.11.

   Anybody succeeded to build PWC for this kernel? If not, what is the
most recent kernel for which the PWC drier can be built with no
problems?