diff --git a/ChangeLog b/ChangeLog
index edc9780723..41b9052c05 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Fri Jan  4 16:24:58 2008  Tanaka Akira  <akr@fsij.org>
+
+	* ext/digest/lib/digest/hmac.rb (Digest::HMAC#initialize): use
+	  String#bytesize to avoid test errors on EUC-JP environment.
+
 Fri Jan  4 14:00:50 2008  Tanaka Akira  <akr@fsij.org>
 
 	* re.c (rb_reg_prepare_re): check string encoding.  Oniguruma doesn't
diff --git a/ext/digest/lib/digest/hmac.rb b/ext/digest/lib/digest/hmac.rb
index cdd537689c..0e3068b0c0 100644
--- a/ext/digest/lib/digest/hmac.rb
+++ b/ext/digest/lib/digest/hmac.rb
@@ -45,7 +45,7 @@ module Digest
 
       block_len = @md.block_length
 
-      if key.length > block_len
+      if key.bytesize > block_len
         key = @md.digest(key)
       end