after i do config my-config
make depend is told to me:

../../../../net/if_spppsubr.c:68: netipx/ipx.h: No such file or directory
../../../../net/if_spppsubr.c:69: netipx/ipx_if.h: No such file or directory

where i may find netipx dirictory ? ( on cvsweb netipx dir is not avalable ) 
( netbsd 1.6 )