gerstensaft version 0.3-4 failed to build on amd64 with GCC-4.6/oneiric

gerstensaft version 0.3-4 failed to build on amd64 with GCC-4.6/oneiric
Link to failed build: https://launchpad.net/ubuntu/+archive/test-rebuild-20110413/+buildjob/2450908

Details about the rebuild:
https://lists.ubuntu.com/archives/ubuntu-devel/2011-April/033042.html

Direct link to the build log: https://launchpad.net/ubuntu/+archive/test-rebuild-20110413/+buildjob/2450908/+files/buildlog_ubuntu-natty-amd64.gerstensaft_0.3-4_FAILEDTOBUILD.txt.gz

This log snippet might be of interest, since it triggered the matcher 'Purging chroot-autobuild'.
Excerpt 2853 lines into the build log:

/build/buildd/gerstensaft-0.3/src/options.c:231: undefined reference to `g_signal_connect_data'
/build/buildd/gerstensaft-0.3/src/options.c:233: undefined reference to `gtk_tooltips_new'
/build/buildd/gerstensaft-0.3/src/options.c:234: undefined reference to `gtk_tooltips_set_tip'
/build/buildd/gerstensaft-0.3/src/options.c:235: undefined reference to `gtk_container_get_type'
/build/buildd/gerstensaft-0.3/src/options.c:235: undefined reference to `g_type_check_instance_cast'
/build/buildd/gerstensaft-0.3/src/options.c:235: undefined reference to `gtk_container_add'
/build/buildd/gerstensaft-0.3/src/options.c:236: undefined reference to `gtk_widget_show'
/build/buildd/gerstensaft-0.3/src/options.c:238: undefined reference to `gtk_widget_show'
collect2: ld returned 1 exit status
make[2]: *** [beer] Error 1
make[2]: Leaving directory `/build/buildd/gerstensaft-0.3/src'
make[1]: *** [all] Error 2
make[1]: Leaving directory `/build/buildd/gerstensaft-0.3'
make: *** [build] Error 2
dpkg-buildpackage: error: debian/rules build gave error exit status 2
******************************************************************************
Build finished at 20110422-2127
FAILED [dpkg-buildpackage died]
Purging chroot-autobuild/build/buildd/gerstensaft-0.3