This package was found to have dev-libs/boost in RDEPEND, but doesn't install either any binary that links against boost libs nor any files that include boost headers. That means it uses boost header-only libraries at compile time only. The tracker bug contains the emerge --info of the test system.
fixed in cvs, thanks for the report. 14 Nov 2009; Markus Meier <maekke@gentoo.org> enblend-3.2.ebuild: boost dep is DEPEND only, bug #293069