Firewall port forward to multicast

I need to be able to forward a unicast stream from outside network to a multicast stream on my home network. I tried setting up a rule that forwards like this, but it is not working. I did exactly as with unicast (which works), but put a multicast address as destination. I am expecting that a lookup on the target address does not give a target interface or something like that. Any ideas how to make this work?

Any chance you tell us which version of openSUSE you want to realize this on?