Ah - I presumed that the debian xz-based packages were using it as an archive, instead of the old 'ar'. But I just looked and you are right, the xz support is f

Ah - I presumed that the debian xz-based packages were using it as an archive, instead of the old 'ar'. But I just looked and you are right, the xz support is for the data.tar.xz that itself is still inside the 'ar' archive format. That is odd. I guess they chose this way for simplicity - far less code needs changing in all the .deb file processing utilities.