diff --git a/ChangeLog b/ChangeLog
index 3cd1f9506e..69c7866581 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Wed Aug  9 16:53:28 2006  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* lib/net/smtp.rb (Net::SMTP::auth_cram_md5): use ord to retrieve
+	  bytes from strings.  a patch from WATANABE Tetsuya
+	  <Tetsuya.WATANABE at nifty.com>.  [ruby-dev:29240]
+
 Tue Aug  8 23:49:06 2006  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* lib/irb/extend-command.rb (IRB::ExtendCommandBundle): pacify
diff --git a/lib/net/smtp.rb b/lib/net/smtp.rb
index 5becf2b36b..f68c47a9a7 100644
--- a/lib/net/smtp.rb
+++ b/lib/net/smtp.rb
@@ -699,8 +699,10 @@ module Net
         isecret = secret + "\0" * (64 - secret.size)
         osecret = isecret.dup
         0.upto(63) do |i|
-          isecret[i] ^= 0x36
-          osecret[i] ^= 0x5c
+          c = isecret[i].ord ^ 0x36
+          isecret[i] = c.chr
+          c = osecret[i].ord ^ 0x5c
+          osecret[i] = c.chr
         end
         tmp = Digest::MD5.digest(isecret + challenge)
         tmp = Digest::MD5.hexdigest(osecret + tmp)