diff --git a/include/libtorrent/broadcast_socket.hpp b/include/libtorrent/broadcast_socket.hpp
index cac0763f4..d899cb614 100644
--- a/include/libtorrent/broadcast_socket.hpp
+++ b/include/libtorrent/broadcast_socket.hpp
@@ -80,6 +80,8 @@ namespace libtorrent
 		void on_receive(socket_entry* s, asio::error_code const& ec
 			, std::size_t bytes_transferred);
 		void open_unicast_socket(io_service& ios, address const& addr);
+		void open_multicast_socket(io_service& ios, address const& addr
+			, bool loopback);
 
 		// these sockets are used to
 		// join the multicast group (on each interface)