--- ${EPREFIX}/usr/portage/app-cdr/iat/iat-0.1.7-r1.ebuild	2012-10-16 21:07:01.000000000 -0700
+++ ${EPREFIX}/usr/portage/app-cdr/iat/iat-0.1.7-r1.ebuild	2013-07-24 20:26:54.000000000 -0700
@@ -16,7 +16,7 @@
 src_configure() {
 	econf  \
 		--disable-dependency-tracking \
-		--includedir=/usr/include/${PN}
+		--includedir=${EPREFIX}/usr/include/${PN}
 }
 
 src_install() {