Is Multicast implemented for server ?

[oloysance]

Hi,
I am developping a COAP server using this library and it seems that the server does not respond to multicast requests even those sent to 224.0.1.187 ipv4, ff02::fd or ff05::fd v6 as it would according to RFC 7390 (2.2) and RFC 7252 (12.8).
I've just used the small sample code below :

        CoapServer server = new CoapServer();
        server.Add(new HelloWorldResource("hello"));
        server.Start();

Then, with a client I just request for .well-known/core on these multicast adresses and no response.
Does this library implements Multicast for server ?
Am I missing something ? does anyone manage to do this with the library ?
Thanks in advance