ruby-activeresource-2.3 version 2.3.11-2 failed to build in oneiric

ruby-activeresource-2.3 version 2.3.11-2 failed to build in oneiric
Link to failed build: https://launchpad.net/ubuntu/+archive/test-rebuild-20110816/+build/2710715

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/2710715/+files/buildlog_ubuntu-oneiric-i386.ruby-activeresource-2.3_2.3.11-2_FAILEDTOBUILD.txt.gz

This log snippet might be of interest, since it triggered the matcher 'Purging chroot-autobuild'.
Excerpt 379 lines into the build log:

install -D -m644 lib/active_resource/formats/json_format.rb /build/buildd/ruby-activeresource-2.3-2.3.11/debian/ruby-activeresource-2.3/usr/lib/ruby/vendor_ruby/active_resource/formats/json_format.rb
install -D -m644 lib/active_resource/formats/xml_format.rb /build/buildd/ruby-activeresource-2.3-2.3.11/debian/ruby-activeresource-2.3/usr/lib/ruby/vendor_ruby/active_resource/formats/xml_format.rb
install -D -m644 lib/active_resource/connection.rb /build/buildd/ruby-activeresource-2.3-2.3.11/debian/ruby-activeresource-2.3/usr/lib/ruby/vendor_ruby/active_resource/connection.rb
install -D -m644 lib/active_resource.rb /build/buildd/ruby-activeresource-2.3-2.3.11/debian/ruby-activeresource-2.3/usr/lib/ruby/vendor_ruby/active_resource.rb
/usr/bin/ruby1.8 -I/usr/lib/ruby/vendor_ruby /usr/lib/ruby/vendor_ruby/gem2deb/test_runner.rb
./test/authorization_test.rb:1:in `require': no such file to load -- abstract_unit (LoadError)
 from ./test/authorization_test.rb:1
 from -e:1:in `require'
 from -e:1
 from -e:1:in `each'
 from -e:1
ERROR: Test "ruby1.8" failed. Exiting.
dh_auto_install: dh_ruby --install /build/buildd/ruby-activeresource-2.3-2.3.11/debian/ruby-activeresource-2.3 returned exit code 1
make: *** [binary] Error 1
dpkg-buildpackage: error: /usr/bin/fakeroot debian/rules binary gave error exit status 2
******************************************************************************
Build finished at 20110820-0729
FAILED [dpkg-buildpackage died]
Purging chroot-autobuild/build/buildd/ruby-activeresource-2.3-2.3.11