Kernel compile problem

OK, now I need to compile the kernel because CMPXCHG is not defined in the generic Knoppix kernel since it was made for 386 processors. No problem, I do make xmenuconfig and change to Athlon. When I stat to compile I envetually get an error message

In file included from gamma_drv.c:34:
drmP.h:932: redefinition of `__cmpxchg'
/usr/src/kernel-source-2.4.22-xfs/include/asm/system.h:244: `__cmpxchg' previously defined here
make[4]: *** [gamma_drv.o] Error 1
make[4]: Leaving directory `/usr/src/kernel-source-2.4.22-xfs/drivers/char/drm'
make[3]: *** [_modsubdir_drm] Error 2
make[3]: Leaving directory `/usr/src/kernel-source-2.4.22-xfs/drivers/char'
make[2]: *** [_modsubdir_char] Error 2
make[2]: Leaving directory `/usr/src/kernel-source-2.4.22-xfs/drivers'
make[1]: *** [_mod_drivers] Error 2
make[1]: Leaving directory `/usr/src/kernel-source-2.4.22-xfs'
make: *** [stamp-build] Error 2


I see a couple other people have seen this in the forum. Has anyone come up with a workaround for this? Based on a Google search, it looks like the 2.4 kernel was sort of transitioning where cmpxchg was to be defined so maybe it is stuck in two places.