diff --git a/ChangeLog b/ChangeLog
index b38c831c7d..a5b058e18d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Wed Sep 29 18:38:14 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* tool/config.sub (x64): regularize only for pc vendor, and strip
+	  useless 64 suffix.
+
 Wed Sep 29 17:53:02 2010  Kenta Murata <mrkn@mrkn.jp>
 
 	* ext/bigdecimal/bigdecimal.c (BIGDECIMAL_ENABLE_VPRINT):
@@ -51,7 +56,7 @@ Tue Sep 28 20:06:14 2010  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 Mon Sep 27 23:30:34 2010  Koichi Sasada  <ko1@atdot.net>
 
-	* insns.def (opt_case_dispatch), vm_insnhelper.c: 
+	* insns.def (opt_case_dispatch), vm_insnhelper.c:
 	  execute the procedures of "when" clauses by bytecode
 	  instead of st_foreach() when the object does not hit
 	  prepared hash.  [ruby-dev:42304]
diff --git a/tool/config.sub b/tool/config.sub
index 611a7b622e..b8d3d323cf 100755
--- a/tool/config.sub
+++ b/tool/config.sub
@@ -4,7 +4,7 @@
 #   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
 #   Free Software Foundation, Inc.
 
-timestamp='2010-09-28'
+timestamp='2010-09-29'
 
 # This file is (in principle) common to ALL GNU software.
 # The presence of a machine in this file suggests that SOME GNU software
@@ -1706,9 +1706,9 @@ case $basic_machine in
 		esac
 		basic_machine=`echo $basic_machine | sed "s/unknown/$vendor/"`
 		;;
-	x86_64*)
+	x86_64-pc)
 		basic_machine=`echo $basic_machine | sed 's/^x86_/x/'`
-		os=`echo $os | sed 's/32/64/'`
+		os=`echo $os | sed '/[a-z]32$/s/32$//;/[a-z]64/s/64$//'`
 		;;
 esac