diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c
--- a/sys/netinet/tcp_usrreq.c
+++ b/sys/netinet/tcp_usrreq.c
@@ -594,7 +594,7 @@
 		goto out;
 	}
 	if (SOLISTENING(so)) {
-		error = EINVAL;
+		error = EOPNOTSUPP;
 		goto out;
 	}
 #ifdef INET