Currently the packaging build feature generates target names in the packaging_build.xml file that are meaningless numbers e.g. N10004
Not only this but everytime you change any aspect of your project packaging the numbers get regenerated.
This makes it useless for allowing user written ant builds to use these targets.
Please make so that in the Project Packaging settings you can assign a user defined target name to each artifact. That way any user written ant file can refer to them via a sensible name that does not change each time.