After merging LibreOffice latest unstable release, 3.4.2.3, portage throws this warning message: QA Notice: epause is not defined in EAPI=3, please file a bug at http://bugs.gentoo.org I guess it's just the case of updating EAPI to 4 or something.
See bug 377891. Marking as a duplicate of *** This bug has been marked as a duplicate of bug 358913 ***