make installworld fails; tzsetup missing -C option

I'm trying to do a remote upgrade of a machine by mounting
it's root filesystem on /mnt using nfs. The build machine
runs a recent 8-STABLE. The target runs 9-CURRENT.

make installworld fails with:

install -o root -g wheel -m 444  /data/FreeBSD/FreeBSD-current/src/share/zoneinfo/../../contrib/tzdata//zone.tab /mnt/usr/share/zoneinfo/
Updating /etc/localtime
tzsetup: illegal option -- C
usage: tzsetup [-ns]
*** Error code 1

Build script does the equivalent of this:
$ mount target:/ /mnt
$ cd /FreeBSD/FreeBSD-current/src
$ make -j4 buildworld && make -j4 buildkernel
$ setenv DESTDIR /mnt
$ make installkernel
$ setenv NO_FSCHG 1
$ make installworld

uname on the build machine:
FreeBSD 8.1-STABLE #1: Tue Aug 10 13:09:59 CEST 2010

- Pieter