diff --git a/VERSION b/VERSION
index c6cd196e6..e74136f3c 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-0.44.8
+0.44.9
diff --git a/examples/token-sale/token_sale.go b/examples/token-sale/token_sale.go
index c6f399b18..9455cb2b6 100644
--- a/examples/token-sale/token_sale.go
+++ b/examples/token-sale/token_sale.go
@@ -228,6 +228,9 @@ func approve(ctx storage.Context, owner, spender []byte, amount int) bool {
 	if !runtime.CheckWitness(owner) || amount < 0 {
 		return false
 	}
+	if len(spender) != 20 {
+		return false
+	}
 	toSpend := storage.Get(ctx, owner).(int)
 	if toSpend < amount {
 		return false