problem on pf @ freebsd 7.0

[CyberSans AirBort]

hello there. sorry if this similar question been asked before in this forum.

my problem is, i install freebsd 7.0 and after that compile the kernel to
enable pf (using the same method like freebsd's handbook said):

device pf
device pflog
device pfsync

options ALTQ
options ALTQ_CBQ
options ALTQ_RED
options ALTQ_RIO
options ALTQ_HFSC
options ALTQ_CDNR
options ALTQ_PRIQ
options ALTQ_NOPCC

and i put everything inside /etc/rc.conf

pf_enable="YES"
pf_rules="/etc/pf.conf"
pf_flags=""
pflog_enable="YES"
pflog_logfile="/var/log/pflog"
pflog_flags=""

and guess what? pf is not loading when startup. i have to manually restarted
the pf using /etc/rc.d/pf restart

is that a bug? i never have this kind of problem when using version 5.* or
6.*