diff --git a/ChangeLog b/ChangeLog
index e777277310..3d1004ff18 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Oct 12 02:15:24 2006  Akinori MUSHA  <knu@iDaemons.org>
+
+	* ext/digest/lib/digest/hmac.rb: Make use of String#bytes.
+
 Thu Oct 12 02:12:31 2006  Akinori MUSHA  <knu@iDaemons.org>
 
 	* ext/digest/digest.c (get_digest_base_metadata): Use an instance
diff --git a/ext/digest/lib/digest/hmac.rb b/ext/digest/lib/digest/hmac.rb
index 3eb83e5ff5..e6870f95c1 100644
--- a/ext/digest/lib/digest/hmac.rb
+++ b/ext/digest/lib/digest/hmac.rb
@@ -54,16 +54,10 @@ module Digest
           ipad = Array.new(BLOCK_LENGTH).fill(0x36)
           opad = Array.new(BLOCK_LENGTH).fill(0x5c)
 
-          i = 0
-          KEY.each_byte { |c|
+          KEY.bytes.each_with_index { |c, i|
             ipad[i] ^= c
             opad[i] ^= c
-            i += 1
           }
-          #KEY.bytes.each_with_index { |c, i|
-          #  ipad[i] ^= c
-          #  opad[i] ^= c
-          #}
 
           @ipad = ipad.inject('') { |s, c| s << c.chr }
           @opad = opad.inject('') { |s, c| s << c.chr }