IP Filter changes in FreeBSD

[Jim Arnold]

I updated my firewall that is using IPF. I went from FreeBSD 4.7 
stable to 4.11 stable. When using 4.7 stable I only had this is my 
rc.conf file:

ipfilter_enable="YES"
ipfilter_program="/sbin/ipf"
ipfilter_rules="/etc/ipf.conf"
ipfilter_flags=""

When I went to 4.11 stable I had to uncomment these options in my 
kernel config file:

options         IPFILTER
options         IPFILTER_LOG

I'm just curious why it worked without the above options in my kernel 
for 4.7 and I had to have them in 4.11?

Thanks,
Jim