SNAT multicast packet

Hi all,

I have a trouble with netfilter. I need to perform a SNAT to outgoing multicast packet. Multicast packet come from private network and i can't annunce this private source network in my routing domain. Because my network manage multicast traffic with PIM-SM protocol and PIM perform RPF (reverse path forwarding), the clients can't see the multicast traffic. I've read that netfilter don't support multicast SNAT, why?

Is there someone can hel me?

Thanks

Best wishes

Paolo