multicasting as a server and listening as a client?

Hello, i have a problem where in i have to use a server, which multicasts packets to all the clients over a port upon a specified event, on lo multicast address, and also accept requests from the clients. i just tried this multicast approach because if i use tcp for this there will be more clients to handle for the server. but seems that as the generic rules of server and client clients can't recieve multicast packets as they didn't bind to the port where in which the server is sending the packets. is there anyway i can solve this. please help!