error building STABLE with BUILD_CLEAN

Hi--

Building STABLE with BUILD_CLEAN set in gar.conf.mk went almost all the 
way, failing when installing during build of linux-image w/following 
messages. (The exact same gar setup succeeded without the BUILD_CLEAN).:

mkdir -p //tmp/build/staging/lnx.img/image//boot
cp work/i386/linux-2.4.19/arch/i386/boot/bzImage 
work/i386/linux-2.4.19/System.m
ap //tmp/build/staging/lnx.img/image//boot
cp: cannot stat `work/i386/linux-2.4.19/arch/i386/boot/bzImage': No such 
file or
  directory
cp: cannot stat `work/i386/linux-2.4.19/System.map': No such file or directory
make[4]: *** [install-lnximg-work/i386/linux-2.4.19/arch/i386/boot/bzImage] 
Erro
r 1
make[4]: Leaving directory `/build/gar/kernel/linux-image'
make[3]: *** [../../kernel/linux-image/cookies/lnximg.d/install] Error 2
...

Sure enough, the package, kernel/linux-image has the following comment in 
its Makefile:

# The above WORKDIR and COOKIEDIR munging make this package incompatible with
# BUILD_CLEAN
BUILD_CLEAN :=
export BUILD_CLEAN

but I don't understand it. Does this mean that BUILD_CLEAN is broken and 
shouldn't be used, or does the above intend to fix the problem for this 
package by unsetting BUILD_CLEAN? If the latter, it didn't work for me.

Please let me know if I'm misusing the variable, and if not, whether I 
should file this as a bug.

Thanks,
Bill

BTW: STABLE builds a perfectly functioning iso with a chroot under the 
latest KNOPPIX; boots on my oldish laptop, wireless works on a net with WEP 
enabled, X works, etc. Minor documentation nit: run time help says that 
browsex and ethereal are available, but they aren't actually built and 
installed.