diff --git a/ChangeLog b/ChangeLog
index aa13e016..2d8b02bf 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2009-04-10  Eric Blake  <ebb9@byu.net>
+
+	submodules: update to latest
+	* submodules/autoconf: Use latest upstream Autoconf.
+
 2009-04-06  Eric Blake  <ebb9@byu.net>
 
 	Work around autoconf 2.63b bug in testsuite.
diff --git a/submodules/autoconf b/submodules/autoconf
index fb069ddf..ef8940d9 160000
--- a/submodules/autoconf
+++ b/submodules/autoconf
@@ -1 +1 @@
-Subproject commit fb069ddf299107885435573544279c07df9d0b50
+Subproject commit ef8940d9b5a3fe2866027f82a535915da3e78829