diff --git a/sys-libs/libcap-ng/libcap-ng-0.7.9.ebuild b/sys-libs/libcap-ng/libcap-ng-0.7.9.ebuild
index 850239d9c2372..e0f8423c7f6e1 100644
--- a/sys-libs/libcap-ng/libcap-ng-0.7.9.ebuild
+++ b/sys-libs/libcap-ng/libcap-ng-0.7.9.ebuild
@@ -22,6 +22,13 @@ DEPEND="${RDEPEND}
 	sys-kernel/linux-headers
 	python? ( >=dev-lang/swig-2 )"
 
+src_prepare() {
+	default
+	if use prefix ; then
+		sed -i "s@cat /usr@cat ${EPREFIX}/usr@" bindings/python*/Makefile.am || die
+	fi
+}
+
 src_configure() {
 	use sparc && replace-flags -O? -O0