[submittodebian] fails with "Version number suggests Ubuntu changes, but Maintainer: does not have Ubuntu address" unless DEBEMAIL overridden

I noticed the change in behaviour between precise->quantal with regards to building the package from source to generate the debdiff; I see this error unless I override DEBEMAIL to not be an @ubuntu.com address.

jamespage@hendrix:~/src/ubuntu/quantal/tiles$ submittodebian
Building using working tree
Building package in normal mode
Looking for a way to retrieve the upstream tarball
Using the upstream tarball that is present in /home/jamespage/src/ubuntu/quantal
Building the package in /home/jamespage/src/ubuntu/quantal/build-area/tiles-2.2.2, using debuild -uc -us -nc -S
 dpkg-buildpackage -rfakeroot -d -us -uc -sa -nc -S
dpkg-buildpackage: source package tiles
dpkg-buildpackage: source version 2.2.2-2ubuntu2
dpkg-buildpackage: source changed by James Page <email address hidden>
 dpkg-source --before-build tiles-2.2.2
dpkg-buildpackage: warning: it is a bad idea to generate a source package without cleaning up first, it might contain undesired files.
 dpkg-source -b tiles-2.2.2
dpkg-source: error: Version number suggests Ubuntu changes, but Maintainer: does not have Ubuntu address
dpkg-source: info: using source format `3.0 (quilt)'
dpkg-buildpackage: error: dpkg-source -b tiles-2.2.2 gave error exit status 255
debuild: fatal error at line 1357:
dpkg-buildpackage -rfakeroot -d -us -uc -sa -nc -S failed
bzr: ERROR: The build failed.
Traceback (most recent call last):
  File "/usr/bin/submittodebian", line 243, in <module>
    main()
  File "/usr/bin/submittodebian", line 226, in main
    build_source_package()
  File "/usr/bin/submittodebian", line 74, in build_source_package
    check_call(cmd)
  File "/usr/lib/python2.7/dist-packages/ubuntutools/subprocess.py", line 77, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['bzr', 'bd', '-S', '--', '-uc', '-us', '-nc']' returned non-zero exit status 3

Not sure what the rationale for changing this was but it takes alot longer to generate the debdiff from a bzr branch than it used to.

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: ubuntu-dev-tools 0.142
ProcVersionSignature: Ubuntu 3.4.0-5.11-generic 3.4.0
Uname: Linux 3.4.0-5-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 2.2.3-0ubuntu4
Architecture: amd64
Date: Tue Jun 19 11:42:14 2012
PackageArchitecture: all
SourcePackage: ubuntu-dev-tools
UpgradeStatus: Upgraded to quantal on 2012-06-11 (8 days ago)