pidgin-sipe version 1.11.2-1 failed to build in oneiric

pidgin-sipe version 1.11.2-1 failed to build in oneiric
Link to failed build: https://launchpad.net/ubuntu/+archive/test-rebuild-20110816/+build/2708163

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/2708163/+files/buildlog_ubuntu-oneiric-amd64.pidgin-sipe_1.11.2-1_FAILEDTOBUILD.txt.gz

This log snippet might be of interest, since it triggered the matcher 'Purging chroot-autobuild'.
Excerpt 1263 lines into the build log:

libtool: compile: x86_64-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I../.. -Werror -Wall -Wextra -Werror=declaration-after-statement -I/usr/include/libxml2 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -DLOCALEDIR=\"/usr/share/locale\" -I./../api -I/usr/include/nss -I/usr/include/nspr -Wall -g -O2 -MT libsipe_core_la-sipe-incoming.lo -MD -MP -MF .deps/libsipe_core_la-sipe-incoming.Tpo -c sipe-incoming.c -fPIC -DPIC -o .libs/libsipe_core_la-sipe-incoming.o
sipe-incoming.c: In function 'process_incoming_invite':
sipe-incoming.c:258:11: error: variable 'is_triggered' set but not used [-Werror=unused-but-set-variable]
cc1: all warnings being treated as errors

make[4]: *** [libsipe_core_la-sipe-incoming.lo] Error 1
make[4]: Leaving directory `/build/buildd/pidgin-sipe-1.11.2/src/core'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory `/build/buildd/pidgin-sipe-1.11.2/src'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/build/buildd/pidgin-sipe-1.11.2'
make[1]: *** [all] Error 2
make[1]: Leaving directory `/build/buildd/pidgin-sipe-1.11.2'
make: *** [build-stamp] Error 2
dpkg-buildpackage: error: debian/rules build gave error exit status 2
******************************************************************************
Build finished at 20110822-1501
FAILED [dpkg-buildpackage died]
Purging chroot-autobuild/build/buildd/pidgin-sipe-1.11.2