diff --git a/configure.ac b/configure.ac
index 9e1d1a16e..a07bfa8d1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -20,7 +20,7 @@
 # ============================
 
 AC_INIT([strongSwan],[5.1.1dr3])
-AM_INIT_AUTOMAKE(tar-ustar)
+AM_INIT_AUTOMAKE([tar-ustar subdir-objects])
 m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES])
 AC_CONFIG_MACRO_DIR([m4/config])
 AC_CONFIG_HEADERS([config.h])