I had the exact same problem last week, with linux-headers-2.6.12-1-686. This seems to be a bug in various linux-headers versions. As I see, this bug is related to:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333842 http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=330081 Also, I fixed this with a different approach, the way it was done up to kernel-image-2.6.11, editing include/linux/version.h, and setting the correct value for UTS_RELEASE. After doing this, I could compile and install with module-assistant, and manually with make (for the cxacru module, merged in 2.6.14). Also of note, not only the target directory were wrong, the modinfo output would show the wrong version too (2.6.12 vs 2.6.12-1-686) -- Martín Ferrari
