Index: /branches/rel_apv_10_7/usr/src/sys/click/app/fastslb/fastslb_tcp.c
===================================================================
--- /branches/rel_apv_10_7/usr/src/sys/click/app/fastslb/fastslb_tcp.c	(revision 39268)
+++ /branches/rel_apv_10_7/usr/src/sys/click/app/fastslb/fastslb_tcp.c	(working copy)
@@ -1232,6 +1232,10 @@
 	}
 #endif
 
+	/* TWSD-637, if the syn seq of fastpcb is not equal to the syn received, update syn packet sequence when forward syn */
+	if (fastpcb->fp_syn_seq != tuples->th->th_seq) {
+		fastpcb->fp_syn_seq = tuples->th->th_seq;
+	}
 	return fasttcp_packet_forwarding(m,fastpcb);
 }