am seeing this problem when trying to compile netsyms.c under 2.1.79.
investigating.
make[2]: Entering directory `/usr/src/linux-2.1.78/net'
gcc -D__KERNEL__ -I/usr/src/linux-2.1.78/include -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer -D__SMP__ -pipe -fno-strength-reduce -m486 -malign-loops=2 -malign-jumps=2 -malign-functions=2 -DCPU=686 -D__SMP__ -DEXPORT_SYMTAB -c netsyms.c
netsyms.c:292: redefinition of `__kstrtab_dev_mc_delete'
netsyms.c:286: `__kstrtab_dev_mc_delete' previously defined here
netsyms.c:292: redefinition of `__ksymtab_dev_mc_delete'
netsyms.c:286: `__ksymtab_dev_mc_delete' previously defined here
make[2]: *** [netsyms.o] Error 1
make[2]: Leaving directory `/usr/src/linux-2.1.78/net'
make[1]: *** [first_rule] Error 2
make[1]: Leaving directory `/usr/src/linux-2.1.78/net'
make: *** [linuxsubdirs] Error 2