Upgraded to open_id_authentication plugin at 00d8bc7f97 and unpacked ruby-openid gem version 2.1.2.

vendor/gems/ruby-openid-2.1.2/lib/openid/extension.rb

@@ -0,0 +1,39 @@
+require 'openid/message'
+
+module OpenID
+  # An interface for OpenID extensions.
+  class Extension < Object
+
+    def initialize
+      @ns_uri = nil
+      @ns_alias = nil
+    end
+
+    # Get the string arguments that should be added to an OpenID
+    # message for this extension.
+    def get_extension_args
+      raise NotImplementedError
+    end
+
+    # Add the arguments from this extension to the provided
+    # message, or create a new message containing only those
+    # arguments.  Returns the message with added extension args.
+    def to_message(message = nil)
+      if message.nil?
+#         warnings.warn('Passing None to Extension.toMessage is deprecated. '
+#                       'Creating a message assuming you want OpenID 2.',
+#                       DeprecationWarning, stacklevel=2)
+        Message.new(OPENID2_NS)
+      end
+      message = Message.new if message.nil?
+
+      implicit = message.is_openid1()
+
+      message.namespaces.add_alias(@ns_uri, @ns_alias, implicit)
+      # XXX python ignores keyerror if m.ns.getAlias(uri) == alias
+
+      message.update_args(@ns_uri, get_extension_args)
+      return message
+    end
+  end
+end