I'm happy to help out with kbuild stuff. But please be a bit more specific :-) I've got most of the infrastructure in place for integrating klibc in the kernel last I looked - but then I got sidetracked while waiting for hpa to do the file-reorg we sort of agreed at.
Did not see that happened so I concluded integration in kernel were low on priority again - so I focussed on other issues.
A few days work (in spare time so calendar timewise it is more) is needed for full integration in kernel. I may even backport some kbuild stuff to klibc to reuse same infrastructure for the programs - but dunno until I take a closer look.