Do get linux kernel sources, untar them to usr/src/linux
under /usr/src/linux, 
make menuconfig; make dep;

return to zaptel code, and recompile.

In file included from zaptel.c:44:
/usr/src/linux/include/linux/module.h:21: linux/modversions.h: No such file or directory
make: *** [zaptel.o] Error 1