--- a/inetd.8
+++ b/inetd.8
@@ -413,6 +413,11 @@ and IPv6 traffic will go to server on
 If you have only one server on
 .Dq tcp6 ,
 only IPv6 traffic will be routed to the server.
+.Pp
+The special
+.Dq tcp46
+parameter can be used for obsolete servers which require to receive IPv4
+connections mapped in an IPv6 socket. Its usage is discouraged.
 .El
 .Sh SEE ALSO
 .Xr fingerd 8 ,
--- a/inetd.c
+++ b/inetd.c
@@ -814,10 +814,14 @@ doconfig(void)
 
 				if (!port) {
 					/* XXX */
+					char *p;
 					strncpy(protoname, sep->se_proto,
 						sizeof(protoname));
-					if (isdigit(protoname[strlen(protoname) - 1]))
-						protoname[strlen(protoname) - 1] = '\0';
+					for (p = protoname; *p; p++)
+						if (isdigit(*p)) {
+							*p = '\0';
+							break;
+						}
 					sp = getservbyname(sep->se_service,
 					    protoname);
 					if (sp == 0) {
@@ -1011,6 +1015,16 @@ setup(struct servtab *sep)
 		    sep->se_service, sep->se_proto);
 		return;
 	}
+	if (strncmp(sep->se_proto, "tcp6", 4) == 0) {
+		if (setsockopt(sep->se_fd, IPPROTO_IPV6, IPV6_V6ONLY, &on,
+			    sizeof (on)) < 0)
+			syslog(LOG_ERR, "setsockopt (IPV6_V6ONLY): %m");
+	} else if (strncmp(sep->se_proto, "tcp46", 5) == 0) {
+		int off = 0;
+		if (setsockopt(sep->se_fd, IPPROTO_IPV6, IPV6_V6ONLY, &off,
+			    sizeof (off)) < 0)
+			syslog(LOG_ERR, "setsockopt (IPV6_V6ONLY): %m");
+	}
 #define	turnon(fd, opt) \
 setsockopt(fd, SOL_SOCKET, opt, &on, sizeof (on))
 	if (strncmp(sep->se_proto, "tcp", 3) == 0 && (options & SO_DEBUG) &&
