Is there any way to have similar mailman functionality using only native Zimbra resources?

My intention is to have the following workflow:

1) User sends an e-mail to distribution list
2) Delegated person receives this e-mail and is asked for approval/reject
3) If approval - Mail is deliverd to distribution list members. If reject - Mail is not delivered to distribution list members.

As far as I understand, milter will not allow me to do exactly this. Is there any way I could achieve this functionality without using any third party?

In case there's no native way to achieve this. Any guide in how to integrate mailman and Zimbra that is up to date?