I do something similar for building an nsis-based win32 installer:
I will check this out tomorrow. Thanks.
Also, you may wish to reconsider whether it is wise to include a debian target/directory directly, or whether you might follow the usual convention for delivering debian source packages:
Mine is a special case however as I will also be the Debian maintainer for the native Debian package and so maintaining an upstream/downstream source directory along with an orig.tar.gz does not make a great deal of sense.