plee-the-bear version 0.5.1-1 failed to build on amd64 with GCC-4.6/oneiric

plee-the-bear version 0.5.1-1 failed to build on amd64 with GCC-4.6/oneiric
Link to failed build: https://launchpad.net/ubuntu/+archive/test-rebuild-20110413/+buildjob/2465255

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/2465255/+files/buildlog_ubuntu-natty-amd64.plee-the-bear_0.5.1-1_FAILEDTOBUILD.txt.gz

This log snippet might be of interest, since it triggered the matcher 'Purging chroot-autobuild'.
Excerpt 1282 lines into the build log:

/usr/include/claw/image.hpp:146:16: note: (perhaps 'typename std::iterator<std::random_access_iterator_tag, Pixel>::difference_type' was intended)
In file included from /usr/include/claw/image.hpp:221:0,
                 from /build/buildd/plee-the-bear-0.5.1/bear-engine/core/src/visual/base_screen.hpp:35,
                 from /build/buildd/plee-the-bear-0.5.1/bear-engine/core/src/visual/gl_screen.hpp:32,
                 from /build/buildd/plee-the-bear-0.5.1/bear-engine/core/src/visual/code/gl_screen.cpp:29:
/usr/include/claw/impl/image.ipp:276:1: error: prototype for 'typename claw::graphic::image::base_iterator<Image, Pixel>::difference_type claw::graphic::image::base_iterator<Image, Pixel>::operator-(const self_type&) const' does not match any in class 'claw::graphic::image::base_iterator<Image, Pixel>'
/usr/include/claw/impl/image.ipp:245:1: error: candidate is: claw::graphic::image::base_iterator<Image, Pixel>::self_type claw::graphic::image::base_iterator<Image, Pixel>::operator-(int) const
make[3]: *** [bear-engine/core/src/visual/CMakeFiles/bear_visual.dir/code/gl_screen.cpp.o] Error 1
make[3]: Leaving directory `/build/buildd/plee-the-bear-0.5.1/build-tree'
make[2]: *** [bear-engine/core/src/visual/CMakeFiles/bear_visual.dir/all] Error 2
make[2]: Leaving directory `/build/buildd/plee-the-bear-0.5.1/build-tree'
make[1]: *** [all] Error 2
make[1]: Leaving directory `/build/buildd/plee-the-bear-0.5.1/build-tree'
make: *** [build-stamp] Error 2
dpkg-buildpackage: error: debian/rules build gave error exit status 2
******************************************************************************
Build finished at 20110425-1523
FAILED [dpkg-buildpackage died]
Purging chroot-autobuild/build/buildd/plee-the-bear-0.5.1