diff -ru linux-orig/net/ipv4/netfilter/ip_nat_helper.c linux-stable/net/ipv4/netfilter/ip_nat_helper.c
--- linux-orig/net/ipv4/netfilter/ip_nat_helper.c	2005-03-02 02:37:49.000000000 -0500
+++ linux-stable/net/ipv4/netfilter/ip_nat_helper.c	2005-04-04 00:22:28.929366600 -0400
@@ -76,11 +76,14 @@
 	 * correction, record it: we don't handle more than one
 	 * adjustment in the window, but do deal with common case of a
 	 * retransmit */
-	if (this_way->offset_before == this_way->offset_after
-	    || before(this_way->correction_pos, seq)) {
-		    this_way->correction_pos = seq;
-		    this_way->offset_before = this_way->offset_after;
-		    this_way->offset_after += sizediff;
+	if (seq != this_way->correction_pos) {
+		seq -= this_way->offset_after;
+		if (this_way->offset_before == this_way->offset_after
+		    || before(this_way->correction_pos, seq)) {
+			this_way->correction_pos = seq;
+			this_way->offset_before = this_way->offset_after;
+			this_way->offset_after += sizediff;
+		}
 	}
 	UNLOCK_BH(&ip_nat_seqofs_lock);