igmpv3/mldv2 equivalent messages

Hi all,

I have a question about multicast router behavior for older version
compatibility.

Regarding the message translation, 7.3.2 of RFC3376 says that IGMPv3
router recognizes v1/v2 Report to IS_EX().

       IGMPv2 Message                IGMPv3 Equivalent
       --------------                -----------------

         Report                        IS_EX( {} )   <--- TO_EX()?

         Leave                         TO_IN( {} )

       IGMP Message                  IGMPv3 Equivalent
       ------------                  -----------------

         v1 Report                      IS_EX( {} )  <--- TO_EX()?

         v2 Report                      IS_EX( {} )  <--- TO_EX()?

As well, 8.3.2 of RFC3810 says;

   MLDv1 Message                 MLDv2 Equivalent
   -------------                 ----------------

      Report                        IS_EX( {} )      <--- TO_EX()?

      Done                          TO_IN( {} )

IS_IN and IS_EX are transmitted as the response of query. I think
these join report messages should be translated as TO_EX(), not
IS_EX(). It is reasonable that leave should be translated as TO_IN()
as mentioned in RFC.

Am I misunderstanding?
--
Hitoshi Asaeda