libpqxx3 version 3.0.2-1 failed to build on i386

libpqxx3 version 3.0.2-1 failed to build on i386
Link to failed build: https://launchpad.net/ubuntu/+archive/test-rebuild-20110413/+buildjob/2459593

Direct link to the build log: https://launchpad.net/ubuntu/+archive/test-rebuild-20110413/+buildjob/2459593/+files/buildlog_ubuntu-natty-i386.libpqxx3_3.0.2-1_FAILEDTOBUILD.txt.gz

This log snippet might be of interest, since it triggered the matcher 'Purging chroot-autobuild'.
Excerpt 1138 lines into the build log:

/bin/bash ../libtool --tag=CXX --mode=compile i686-linux-gnu-g++ -DHAVE_CONFIG_H -I../../../include -I../include -I/usr/include/postgresql -g -O2 -D_REENTRANT -Werror -MT connection_base.lo -MD -MP -MF .deps/connection_base.Tpo -c -o connection_base.lo ../../../src/connection_base.cxx
libtool: compile: i686-linux-gnu-g++ -DHAVE_CONFIG_H -I../../../include -I../include -I/usr/include/postgresql -g -O2 -D_REENTRANT -Werror -MT binarystring.lo -MD -MP -MF .deps/binarystring.Tpo -c ../../../src/binarystring.cxx -fPIC -DPIC -o .libs/binarystring.o
libtool: compile: i686-linux-gnu-g++ -DHAVE_CONFIG_H -I../../../include -I../include -I/usr/include/postgresql -g -O2 -D_REENTRANT -Werror -MT connection_base.lo -MD -MP -MF .deps/connection_base.Tpo -c ../../../src/connection_base.cxx -fPIC -DPIC -o .libs/connection_base.o
In file included from ../../../src/binarystring.cxx:17:0:
../../../include/pqxx/compiler-internal.hxx:79:29: error: 'ptrdiff_t' does not name a type
In file included from ../../../src/connection_base.cxx:18:0:
../../../include/pqxx/compiler-internal.hxx:79:29: error: 'ptrdiff_t' does not name a type
make[2]: *** [binarystring.lo] Error 1
make[2]: *** Waiting for unfinished jobs....
make[2]: *** [connection_base.lo] Error 1
make[2]: Leaving directory `/build/buildd/libpqxx3-3.0.2/debian/build/src'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/build/buildd/libpqxx3-3.0.2/debian/build'
make: *** [build-stamp] Error 2
dpkg-buildpackage: error: debian/rules build gave error exit status 2
******************************************************************************
Build finished at 20110415-0053
FAILED [dpkg-buildpackage died]
Purging chroot-autobuild/build/buildd/libpqxx3-3.0.2