diff --git a/lib/pdu.js b/lib/pdu.js
index b7e479b..d46ac9d 100644
--- a/lib/pdu.js
+++ b/lib/pdu.js
@@ -59,7 +59,7 @@ PDU.fromStream = function(stream, command_length) {
 		return false;
 	}
 	var commandLengthBuffer = Buffer.alloc(4);
-	commandLengthBuffer.writeUInt32BE(command_length);
+	commandLengthBuffer.writeUInt32BE(command_length, 0);
 	var pduBuffer = Buffer.concat([commandLengthBuffer, buffer]);
 
 	return new PDU(pduBuffer);