obconf version 2.0.3-3ubuntu2 failed to build in oneiric

obconf version 2.0.3-3ubuntu2 failed to build in oneiric
Link to failed build: https://launchpad.net/ubuntu/+archive/test-rebuild-20110816/+build/2706589

Details about the rebuild:
http://people.ubuntuwire.org/~wgrant/rebuild-ftbfs-test/test-rebuild-20110816-oneiric.html

Direct link to the build log: https://launchpad.net/ubuntu/+archive/test-rebuild-20110816/+build/2706589/+files/buildlog_ubuntu-oneiric-amd64.obconf_2.0.3-3ubuntu2_FAILEDTOBUILD.txt.gz

This log snippet might be of interest, since it triggered the matcher 'Purging chroot-autobuild'.
Excerpt 868 lines into the build log:

checking pkg-config is at least version 0.9.0... yes
checking for OPENBOX... configure: error: Package requirements (obrender-3.0 >= 3.4.2 obparser-3.0 >= 3.4.2) were not met:

No package 'obrender-3.0' found
No package 'obparser-3.0' found

Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

Alternatively, you may set the environment variables OPENBOX_CFLAGS
and OPENBOX_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.

make: *** [configure-stamp] Error 1
dpkg-buildpackage: error: debian/rules build gave error exit status 2
******************************************************************************
Build finished at 20110822-0929
FAILED [dpkg-buildpackage died]
Purging chroot-autobuild/build/buildd/obconf-2.0.3