Current method of installation (copying the files) causes crashes in the plugin. We should either use src_install() { emake DESTDIR="${D}" install } or just omit the src_install() function. Although some work has been made to prevent it, we should use the standard make install method... See: http://gitweb.freedesktop.org/?p=swfdec/swfdec-mozilla.git;a=commitdiff;h=85bb0aaad68236d0953f913e0af149635fcd2ce7
If you claim that something crashes, then post the errors. Also emerge --info is required for bugs. Thanks.