kernel define changed after 2.6.12

compile errot cause of define in linux/netlink.h:netlink_kernel_create changed .
but i don't know how to change the src....8-(


2.6.13
extern struct sock *netlink_kernel_create(int unit, void (*input)(struct sock *sk, int len));
2.6.14
extern struct sock *netlink_kernel_create(int unit, unsigned int groups, void (*input)(struct sock *sk, int len
), struct module *module);
2.6.15
extern struct sock *netlink_kernel_create(int unit, unsigned int groups, void (*input)(struct sock *sk, int len
), struct module *module);