--- socket.c
+++ socket.c
@@ -71,6 +71,13 @@
 	int		num_fd;
 	int		isipv4;
 
+	if (config.bind_ipv4 && config.bind_ipv6) {
+			if (*config.ipv4 == '\0' && *config.ipv6 != '\0')
+					fatal("error: while binding port on ipv4 and ipv6, if option 'bind_ipv4_host' is set, bind_ipv6_host must be set too");
+			if (*config.ipv4 != '\0' && *config.ipv6 == '\0')
+					fatal("error: while binding port on ipv4 and ipv6, if option 'bind_ipv6_host' is set, bind_ipv4_host must be set too");
+	}
+
 	if (config.port == 0)
 		config.port = DFLT_PORT;
 	(void) snprintf(strport, sizeof(strport), "%d", config.port);
@@ -80,13 +87,25 @@
 		num_fd++;
 	if (config.bind_ipv6)
 		num_fd++;
-		
+
+	if (config.bind_ipv4 && config.bind_ipv6
+			&& *config.ipv4 == '\0' && *config.ipv6 == '\0')
+			num_fd--;
+
 	i = 0;
 	(void) memset(s, 0, sizeof(s));
 	s[0].fd = s[1].fd = 0;
 	while (i < num_fd) {
 		(void) memset(&hints[i], 0, sizeof(struct addrinfo));
-		hints[i].ai_family = (i == 0 && config.bind_ipv4) ? PF_INET : PF_INET6;
+
+		if (config.bind_ipv4 && config.bind_ipv6
+				&& *config.ipv4 == '\0' && *config.ipv6 == '\0')
+				hints[i].ai_family = PF_UNSPEC;
+		else if (i == 0 && config.bind_ipv4)
+				hints[i].ai_family = PF_INET;
+		else
+				hints[i].ai_family = PF_INET6;
+
 		hints[i].ai_socktype = SOCK_STREAM;
 		hints[i].ai_flags = AI_PASSIVE;
 		if (i == 0 && config.bind_ipv4) {
@@ -113,12 +132,8 @@
 			fatal("setsockopt() failed for (%s) %s", ip_add, (i == 0 && config.bind_ipv4) ? "IPv4" : "IPv6");
 		}
 		if (bind(s[i].fd, (struct sockaddr *) res->ai_addr, res->ai_addrlen) < 0) {
-			(void) close(s[i].fd);
-#if defined(__linux__)
-			if (i == 1)
-				fatal("could not bind to IPv6, possibly because of\nLinux's ``feature'' to bind to IPv4 also.\nTry -b or binding to specific IPv6 address via -C\nif you're using IPv6 with Linux 2.4\nError message");
-#endif /* __linux__ */
-			fatal("bind() failed for (%s) %s", ip_add, (i == 0 && config.bind_ipv4) ? "IPv4" : "IPv6");
+				(void) close(s[i].fd);
+				fatal("bind() failed for (%s) %s", ip_add, (i == 0 && config.bind_ipv4) ? "IPv4" : "IPv6");
 		}
 		if (listen(s[i].fd, config.backlog) != 0) {
 			(void) close(s[i].fd);