diff --git a/m4/xalloc.m4 b/m4/xalloc.m4
index 27c0a7b63..0c14045ba 100644
--- a/m4/xalloc.m4
+++ b/m4/xalloc.m4
@@ -1,4 +1,4 @@
-# xalloc.m4 serial 4
+# xalloc.m4 serial 6
 dnl Copyright (C) 2002-2003 Free Software Foundation, Inc.
 dnl This file is free software, distributed under the terms of the GNU
 dnl General Public License.  As a special exception to the GNU General