Please add the necessary @... things to the src_unpack() so that it will light up in the eclass and become clear which phase functions are exported.
/var/cvsroot/gentoo-x86/eclass/ChangeLog,v <-- ChangeLog new revision: 1.666; previous revision: 1.665 /var/cvsroot/gentoo-x86/eclass/vcs-snapshot.eclass,v <-- vcs-snapshot.eclass new revision: 1.6; previous revision: 1.5