diff --git a/lib/nop.c b/lib/nop.c
index f828822..f4fec90 100644
--- a/lib/nop.c
+++ b/lib/nop.c
@@ -21,6 +21,7 @@
 #endif
 
 #include <stdio.h>
+#include <stdlib.h>
 #include "iscsi.h"
 #include "iscsi-private.h"
 
@@ -146,11 +147,14 @@ iscsi_process_nop_out_reply(struct iscsi_context *iscsi, struct iscsi_pdu *pdu,
 	if (iscsi->waitpdu->cmdsn == iscsi->min_cmdsn_waiting) {
 		ISCSI_LOG(iscsi, 2, "Oldest element in waitqueue is unchanged since last NOP-In (iscsi->min_cmdsn_waiting %08x)",
 		          iscsi->min_cmdsn_waiting); 
+		if (getenv("LIBISCSI_IGNORE_NOP_OUT_ON_STUCK_WAITPDU_QUEUE") == NULL) {
+			iscsi->nops_in_flight = 0;
+		}
+	} else {
+		iscsi->nops_in_flight = 0;
 	}
 	iscsi->min_cmdsn_waiting = iscsi->waitpdu->cmdsn;
 
-	iscsi->nops_in_flight = 0;
-
 	if (pdu->callback == NULL) {
 		return 0;
 	}