trouble building FreeBSD 8.1 amd64 kernel with pfsync support

[Cameron Simpson]

I'm trying to build a kernel for a pair of firewalls which will be using
CARP and pfsync for redundancy. Since I'm new to FreeBSD the config is
based on the GENERIC config, thus:

  include GENERIC
  ident NEW_FIREWALL
  device carp
  ##device pfsync

and issuing the build like this:

  # cd /usr/src
  # time make buildkernel KERNCONF=NEW_FIREWALL && echo YES

With the config above (CARP but no pfsync) it builds just fine
and boots and runs happily; I've got CARP configured.

If I uncomment the "devic pfsync" the build aborts at link time ending thus:

  MAKE=make sh /usr/src/sys/conf/newvers.sh NEW_FIREWALL cc -c -O2 -frename-registers -pipe -fno-strict-aliasing  -std=c99 -g -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes -Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual  -Wundef -Wno-pointer-sign -fformat-extensions -nostdinc  -I. -I/usr/src/sys -I/usr/src/sys/contrib/altq -D_KERNEL -DHAVE_KERNEL_OPTION_HEADERS -include opt_global.h -fno-common -finline-limit=8000 --param inline-unit-growth=100 --param large-function-growth=1000 -fno-omit-frame-pointer -mcmodel=kernel -mno-red-zone  -mfpmath=387 -mno-sse -mno-sse2 -mno-sse3 -mno-mmx -mno-3dnow  -msoft-float -fno-asynchronous-unwind-tables -ffreestanding -fstack-protector -Werror  vers.c
  linking kernel.debug
  in_proto.o(.data+0x698): undefined reference to `pfsync_input'
  *** Error code 1

  Stop in /usr/obj/usr/src/sys/NEW_FIREWALL.
  *** Error code 1

  Stop in /usr/src.
  *** Error code 1

  Stop in /usr/src.

  real    11m33.795s
  user    7m19.405s
  sys     0m40.068s

Am I doing something obviously wrong here?

Cheers,
-- 
Cameron Simpson <cs at zip.com.au> DoD#743
http://www.cskk.ezoshosting.com/cs/

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