paxtest version 1:0.9.9-1 failed to build in oneiric

paxtest version 1:0.9.9-1 failed to build in oneiric
Link to failed build: https://launchpad.net/ubuntu/+archive/test-rebuild-20110816/+build/2707617

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/2707617/+files/buildlog_ubuntu-oneiric-i386.paxtest_1%3A0.9.9-1_FAILEDTOBUILD.txt.gz

This log snippet might be of interest, since it triggered the matcher 'Purging chroot-autobuild'.
Excerpt 300 lines into the build log:

gcc -O2 -Wa,--noexecstack -D_FORTIFY_SOURCE=0 -DRUNDIR=\"/usr/lib/paxtest\" -fno-stack-protector -m32 -o anonmap.o -c anonmap.c
<command-line>:0:0: warning: "_FORTIFY_SOURCE" redefined [enabled by default]
<built-in>:0:0: note: this is the location of the previous definition
gcc -m32 -lpthread -o anonmap body.o anonmap.o
body.o: In function `main':
body.c:(.text.startup+0xc0): undefined reference to `pthread_create'
body.c:(.text.startup+0xd9): undefined reference to `pthread_kill'
collect2: ld returned 1 exit status
make[2]: *** [anonmap] Error 1
rm shlibtest.o shlibtest2.o
make[2]: Leaving directory `/build/buildd/paxtest-0.9.9'
make[1]: *** [linux32] Error 2
make[1]: Leaving directory `/build/buildd/paxtest-0.9.9'
make: *** [build-stamp] Error 2
dpkg-buildpackage: error: debian/rules build gave error exit status 2
******************************************************************************
Build finished at 20110820-1253
FAILED [dpkg-buildpackage died]
Purging chroot-autobuild/build/buildd/paxtest-0.9.9