diff --git a/configure.ac b/configure.ac
index b5e3d240..cfbdd27e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -5,7 +5,7 @@ AC_CONFIG_SRCDIR([src/main.cc])
 AC_CONFIG_HEADERS([config.h])
 AC_CONFIG_MACRO_DIR([m4])
 
-AM_INIT_AUTOMAKE([1.9])
+AM_INIT_AUTOMAKE([1.9 subdir-objects])
 AM_MAINTAINER_MODE