Upstream distributes v86d source as a bzipped tarball.
Such tarballs are not (yet) accepted by the Debian archive.
Thus one needs to repack the tarball with the following command
bzip2 -dc v86d-0.1.5.tar.bz2 |gzip -9 > v86d_0.1.5.orig.tar.gz
(the 0.1.5 needs to be replaced by the real version of course).

This package uses quilt for patch management, for more information see
the file /usr/share/doc/quilt/README.source in the quilt package.