Can't load ip_tables module

[JF Rameau]

I just compiled a 2.4.18 stock kernel and configured netfilter to be 
used as modules but when i try to load iptable_filter module using 
modprobe, i get the following message :

/lib/modules/2.4.18/kernel/net/ipv4/netfilter/iptable_filter.o : 
unresolved symbol nf_register_hook
/lib/modules/2.4.18/kernel/net/ipv4/netfilter/iptable_filter.o : 
unresolved symbol nf_unregister_hook

Did i miss something during kernel configuration ?

GCC 2.95.3

Thanks for your help