diff --git a/geant/geant-4.9.1_p01.ebuild b/geant/geant-4.9.1_p01.ebuild
index b60230b..b106dbd 100644
--- a/geant/geant-4.9.1_p01.ebuild
+++ b/geant/geant-4.9.1_p01.ebuild
@@ -141,6 +141,15 @@ g4_create_env_script() {
 		LDPATH=${G4LIB}
 		CLHEP_BASE_DIR=${CLHEP_BASE_DIR}
 	EOF
+
+	# detailed data file locations
+	if $(use data); then
+		export G4LEVELGAMMADATA="${G4DATA}/PhotonEvaporation2.0"
+		export G4RADIOACTIVEDATA="${G4DATA}/RadioactiveDecay3.2"
+		export G4LEDATA="${G4DATA}/G4EMLOW5.1"
+		export G4NEUTRONHPCROSSSECTIONS="${G4DATA}/G4NDL3.12"
+	fi
+
 	# read env variables defined upto now
 	printenv | grep ^G4 | uniq >> ${g4env}
 
@@ -195,8 +204,8 @@ src_install() {
 }
 
 pkg_postinst() {
-	elog "Geant4 projects are by default expected in each user's "
-	elog "If you want to change, set \$G4WORKDIR to another directory"
+	elog "Geant4 projects are by default build in $G4WORKDIR."
+	elog "If you want to change, set \$G4WORKDIR to another directory."
 	elog
 	elog "Help us to improve the ebuild and dependencies in"
 	elog "http://bugs.gentoo.org/show_bug.cgi?id=212221"