(can't sleep. Clowns will eat me) Need to compile and install binutils-sparc (is not built from the binutils package for some reason unknown to me right now). Then install dpkg-cross, and import ldso, libc6, and libc6-dev debs from Sparc. Then symlink /usr/local/sparc-linux/[include|lib] into /usr/sparc-linux/. Then tweak gcc-m68k-linux into building for sparc and depending on binutils-sparc instead of binutils-sparc-linux.
Assuming this works, we would somehow need a libc6-dev crosscompile package built for each supported arch and a few other minor package fixes. I think I'm starting to drift off-topic.. Sometime tomorrow I'll post a compressed log of kernel-source-2.2.17 compiling for people to look at. I'm on a dialup connection for the time being though. Then I have a question of testing the kernel. How should I write a boot floppy with the kernel, assuming it builds?