diff --git a/ChangeLog b/ChangeLog
index 6cfbe770a7..e90bb25625 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Aug 22 19:21:00 2006  Minero Aoki  <aamine@loveruby.net>
+
+	* lib/net/smtp.rb: parameter `to_addrs' might be an Array,
+	  .flatten is required. [ruby-dev:29316]
+
 Tue Aug 22 12:35:57 2006  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* ext/nkf/lib/kconv.rb (Kconv::RegexpEucjp): fix regexp for
diff --git a/lib/net/smtp.rb b/lib/net/smtp.rb
index ab9c1afb88..29b7c0b71c 100644
--- a/lib/net/smtp.rb
+++ b/lib/net/smtp.rb
@@ -794,7 +794,7 @@ module Net
 
     def rcptto_list(to_addrs)
       raise ArgumentError, 'mail destination not given' if to_addrs.empty?
-      to_addrs.each do |addr|
+      to_addrs.flatten.each do |addr|
         rcptto addr
       end
     end