diff --git a/sys/netinet/tcp_timewait.c b/sys/netinet/tcp_timewait.c
--- a/sys/netinet/tcp_timewait.c
+++ b/sys/netinet/tcp_timewait.c
@@ -218,12 +218,13 @@
 	/*
 	 * If a new connection request is received
 	 * while in TIME_WAIT, drop the old connection
-	 * and start over if the sequence numbers
-	 * are above the previous ones.
+	 * and start over if the sequence number
+	 * is different from the previous initial
+	 * sequence number.
 	 * Allow UDP port number changes in this case.
 	 */
 	if (((thflags & (TH_SYN | TH_ACK)) == TH_SYN) &&
-	    SEQ_GT(th->th_seq, tp->rcv_nxt)) {
+	    th->th_seq != tp->irs) {
 		/*
 		 * In case we can't upgrade our lock just pretend we have
 		 * lost this packet.