diff --git a/lib/protocol/uint64_t.js b/lib/protocol/uint64_t.js
index 2be9664..98aa293 100644
--- a/lib/protocol/uint64_t.js
+++ b/lib/protocol/uint64_t.js
@@ -350,6 +350,8 @@ uint64_t.prototype.toOctets = function uint64_t_toOctets() {
 		v.hi >>>= 8;
 	}
 
+	while (a.length<8) a.unshift(0);
+
 	return (a);
 };