diff --git a/ChangeLog b/ChangeLog
index bf48c1dec6..1e26d86295 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Sep 23 23:08:41 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* tool/config.sub: mingw64 should use x86_64.  [ruby-core:32514]
+
 Thu Sep 23 21:40:40 2010  wanabe  <s.wanabe@gmail.com>
 
 	* ext/socket/raddrinfo.c (init_addrinfo, inspect_sockaddr): suppress
@@ -15,7 +19,7 @@ Thu Sep 23 18:54:39 2010  wanabe  <s.wanabe@gmail.com>
 	* win32/mkexports.rb (Exports::Mingw64): added.
 
 	* win32/mkexports.rb (Exports::Mingw32): renamed from Exports::Mingw.
-  
+
 Thu Sep 23 09:01:28 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* vm_insnhelper.c (vm_cref_push): no outer cref is needed for proc
diff --git a/tool/config.sub b/tool/config.sub
index 0e1ffea92d..73ec982594 100755
--- a/tool/config.sub
+++ b/tool/config.sub
@@ -4,7 +4,7 @@
 #   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
 #   Free Software Foundation, Inc.
 
-timestamp='2009-04-17'
+timestamp='2010-09-23'
 
 # This file is (in principle) common to ALL GNU software.
 # The presence of a machine in this file suggests that SOME GNU software
@@ -724,7 +724,7 @@ case $basic_machine in
 		os=-mingw32
 		;;
 	mingw64)
-		basic_machine=i386-pc
+		basic_machine=x86_64-pc
 		os=-mingw64
 		;;
 	mingw32ce)