i dont think sys-libs/db makes it into stage1 or stage2, so right away USE=bootstrap doesnt make much sense. even then, if it needs libtool or similar autotools, it should depend on them and assume they're available as none of those packages depend on sys-libs/db.
I can confirm that this package does not appear in stage1 or stage2, so feel free to whack the USE flag.
ive dropped it from all db-4.6 and db-4.7 ebuilds ... if there are no regressions, i'll drop it from the rest http://sources.gentoo.org/sys-libs/db/db-4.6.21_p1.ebuild?r1=1.2&r2=1.3 http://sources.gentoo.org/sys-libs/db/db-4.6.21_p3.ebuild?r1=1.1&r2=1.2 http://sources.gentoo.org/sys-libs/db/db-4.6.21_p3-r1.ebuild?r1=1.3&r2=1.4 http://sources.gentoo.org/sys-libs/db/db-4.7.25.ebuild?r1=1.2&r2=1.3 http://sources.gentoo.org/sys-libs/db/db-4.7.25_p1.ebuild?r1=1.1&r2=1.2 http://sources.gentoo.org/sys-libs/db/db-4.7.25_p1-r1.ebuild?r1=1.4&r2=1.5
no reports, so punt the rest http://sources.gentoo.org/sys-libs/db/db-4.2.52_p4-r2.ebuild?r1=1.15&r2=1.16 http://sources.gentoo.org/sys-libs/db/db-4.2.52_p5-r1.ebuild?r1=1.8&r2=1.9 http://sources.gentoo.org/sys-libs/db/db-4.2.52_p5.ebuild?r1=1.2&r2=1.3 http://sources.gentoo.org/sys-libs/db/db-4.3.29-r2.ebuild?r1=1.19&r2=1.20 http://sources.gentoo.org/sys-libs/db/db-4.3.29_p1-r1.ebuild?r1=1.10&r2=1.11 http://sources.gentoo.org/sys-libs/db/db-4.3.29_p1.ebuild?r1=1.2&r2=1.3 http://sources.gentoo.org/sys-libs/db/db-4.4.20_p4-r1.ebuild?r1=1.2&r2=1.3 http://sources.gentoo.org/sys-libs/db/db-4.4.20_p4.ebuild?r1=1.6&r2=1.7 http://sources.gentoo.org/sys-libs/db/db-4.5.20_p2-r1.ebuild?r1=1.10&r2=1.11 http://sources.gentoo.org/sys-libs/db/db-4.5.20_p2.ebuild?r1=1.26&r2=1.27
