How are we supposed to test locally a package that has a additional dependency on the target ppa?

I've learned that it's possible to add a ppa dependency to other ppa's on launchpad, so that the build-dependencie of packages built with that target can be searched and satisfied like that; which is handy.

However, how am i supposed to test this locally? Currectly i was doing the bzr dailydeb to download the source package from the ppa, repackaging it with dbuild and finally building with pbuild; like so:

dailydeb --allow-fallback-to-native dosbox.recipe result
cd result
cd dosbox-\{debupstream\}+\{date\}/ && dpkg-buildpackage -rfakeroot -d -us -uc -i -I -S && cd .. && sudo pbuilder build dosbox_0.74+20121231.dsc

This so i could change the source inside the cd dosbox-{debupstream}+{date} dir and then just needed to repeat the last line to test things out.

However pbuild fails locally with unsatisfied dependencies with this. Is there any way to add the missing ppa so that pbuilder is satisfied?