--- a/configure.ac  2019-01-20 20:28:01.309231507 +0100
+++ b/configure.ac  2019-01-20 20:31:54.927978927 +0100
@@ -137,7 +137,7 @@
 
 # Find out where the session service file goes
 # The sad sed hack is recomended by section 27.10 of the automake manual.
-DBUS_SESSION_SERVICE_DIR=`pkg-config --variable session_bus_services_dir dbus-1 | sed -e 's,/usr/share,${datarootdir},g'`
+DBUS_SESSION_SERVICE_DIR=`pkg-config --variable session_bus_services_dir dbus-1 --define-variable 'datadir=${datadir}'`
 AC_SUBST(DBUS_SESSION_SERVICE_DIR)
 
 dnl ---------------------------------------------------------------------------