diff --git a/legacy/embryo/configure.ac b/legacy/embryo/configure.ac
index a055b71d9e..680fe35734 100644
--- a/legacy/embryo/configure.ac
+++ b/legacy/embryo/configure.ac
@@ -9,8 +9,9 @@ AC_CANONICAL_BUILD
 AC_CANONICAL_HOST
 AC_ISC_POSIX
 
-AM_INIT_AUTOMAKE(1.6 dist-bzip2)
-AM_CONFIG_HEADER(config.h)
+AM_INIT_AUTOMAKE([1.6 dist-bzip2])
+AM_CONFIG_HEADER([config.h])
+m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
 
 AC_LIBTOOL_WIN32_DLL
 define([AC_LIBTOOL_LANG_CXX_CONFIG], [:])dnl