Comment 2 for bug 179588

The problem is in debian/rules; change:

common-install-arch::
        mkdir -p debian/tmp/usr/lib/mozilla-firefox/plugins
        cd debian/tmp/usr/lib/mozilla-firefox/plugins && \
                ln -s ../../mozilla/plugins/libswfdecmozilla.so .

to:

common-install-arch::
        mkdir -p debian/tmp/usr/lib/firefox/plugins
        cd debian/tmp/usr/lib/firefox/plugins && \
                ln -s ../../mozilla/plugins/libswfdecmozilla.so .

Also remember updating swfdec-mozilla.install accordingly. This works also for swfdec-mozilla-0.5.5.
Incidentally, I noticed the djvulibre-plugin has the same problem. If someone with upload privileges can fix... ?

Cheers,
Matteo