Well, I upgraded tools to 3.09.0, so that's one problem out of the way
(though slightly annoying .. ah well).

Here's my latest error :-)

make[1]: Entering directory `/home/jonathan/dst/kernel'
../ocaml/bin/ocamlc -output-obj -o bytekernel.o asm.mli keyboard.ml
VFS.ml PCI.ml busManager.ml bytekernel.ml
Error while linking /home/jonathan/dst/ocaml/lib/ocaml/stdlib.cma(Pervasives):
Reference to undefined global `End_of_file'
make[1]: *** [bytekernel.o] Error 2

Obviously, I've removed some code that defines this somewhere (hope I
don't have to make too many changes to my custom environment). Any
hints?

Jonathan