diff --git a/ares/configure.ac b/ares/configure.ac
index 673f41796..65c251558 100644
--- a/ares/configure.ac
+++ b/ares/configure.ac
@@ -15,7 +15,7 @@ CARES_CHECK_OPTION_OPTIMIZE
 CARES_CHECK_OPTION_WARNINGS
 CARES_CHECK_OPTION_CURLDEBUG
 
-CARES_CHECK_PATH_SEPARATOR
+CARES_CHECK_PATH_SEPARATOR_REQUIRED
 
 dnl SED is mandatory for configure process and libtool.
 dnl Set it now, allowing it to be changed later.
diff --git a/ares/m4/cares-system.m4 b/ares/m4/cares-system.m4
index 39b3c859a..f0adc8975 100644
--- a/ares/m4/cares-system.m4
+++ b/ares/m4/cares-system.m4
@@ -1,7 +1,7 @@
 #***************************************************************************
 # $Id$
 #
-# Copyright (C) 2008 by Daniel Stenberg et al
+# Copyright (C) 2008 - 2009 by Daniel Stenberg et al
 #
 # Permission to use, copy, modify, and distribute this software and its
 # documentation for any purpose and without fee is hereby granted, provided
@@ -16,7 +16,7 @@
 #***************************************************************************
 
 # File version for 'aclocal' use. Keep it a single number.
-# serial 2
+# serial 3
 
 
 dnl CARES_CHECK_PATH_SEPARATOR
@@ -72,3 +72,12 @@ AC_DEFUN([CARES_CHECK_PATH_SEPARATOR], [
 ])
 
 
+dnl CARES_CHECK_PATH_SEPARATOR_REQUIRED
+dnl -------------------------------------------------
+dnl Use this to ensure that the path separator check
+dnl macro is only expanded and included once.
+
+AC_DEFUN([CARES_CHECK_PATH_SEPARATOR_REQUIRED], [
+  AC_REQUIRE([CARES_CHECK_PATH_SEPARATOR])dnl
+])
+
diff --git a/configure.ac b/configure.ac
index 095ec64de..dd53b2ed4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -43,7 +43,7 @@ CURL_CHECK_OPTION_OPTIMIZE
 CURL_CHECK_OPTION_WARNINGS
 CURL_CHECK_OPTION_CURLDEBUG
 
-CURL_CHECK_PATH_SEPARATOR
+CURL_CHECK_PATH_SEPARATOR_REQUIRED
 
 dnl SED is mandatory for configure process and libtool.
 dnl Set it now, allowing it to be changed later.
diff --git a/m4/curl-system.m4 b/m4/curl-system.m4
index 3f8bb19f9..dcefde91d 100644
--- a/m4/curl-system.m4
+++ b/m4/curl-system.m4
@@ -5,7 +5,7 @@
 #                            | (__| |_| |  _ <| |___
 #                             \___|\___/|_| \_\_____|
 #
-# Copyright (C) 1998 - 2008, Daniel Stenberg, <daniel@haxx.se>, et al.
+# Copyright (C) 1998 - 2009, Daniel Stenberg, <daniel@haxx.se>, et al.
 #
 # This software is licensed as described in the file COPYING, which
 # you should have received as part of this distribution. The terms
@@ -22,7 +22,7 @@
 #***************************************************************************
 
 # File version for 'aclocal' use. Keep it a single number.
-# serial 2
+# serial 3
 
 
 dnl CURL_CHECK_PATH_SEPARATOR
@@ -77,3 +77,13 @@ AC_DEFUN([CURL_CHECK_PATH_SEPARATOR], [
   AC_SUBST([PATH])
 ])
 
+
+dnl CURL_CHECK_PATH_SEPARATOR_REQUIRED
+dnl -------------------------------------------------
+dnl Use this to ensure that the path separator check
+dnl macro is only expanded and included once.
+
+AC_DEFUN([CURL_CHECK_PATH_SEPARATOR_REQUIRED], [
+  AC_REQUIRE([CURL_CHECK_PATH_SEPARATOR])dnl
+])
+