bzr branch -r $STAGE_OVERLAY_REVNO[$1] $FSB_OVERLAY_BASE/$1 $build_dir/var/portage/$1 || die "Failed to branch overlay ${(qqq)1}"
sed -i "s|PORTDIR_OVERLAY=[\"']|&/var/portage/$1 |" $build_dir/etc/portage/make.conf || die