--- old/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/objects/NativeArrayBuffer.java	2015-03-16 16:01:32.000000000 +0100
+++ new/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/objects/NativeArrayBuffer.java	2015-03-16 16:01:32.000000000 +0100
@@ -26,7 +26,9 @@
 package jdk.nashorn.internal.objects;
 
 import static jdk.nashorn.internal.runtime.ECMAErrors.typeError;
+
 import java.nio.ByteBuffer;
+
 import jdk.nashorn.internal.objects.annotations.Attribute;
 import jdk.nashorn.internal.objects.annotations.Constructor;
 import jdk.nashorn.internal.objects.annotations.Function;
@@ -101,7 +103,9 @@
         }
 
         if (args.length == 0) {
-            throw new RuntimeException("missing length argument");
+            //For ES6 rev28+ we should throw a TypeError here. None of the other runtimes
+            //currently do it, though, so I have chosen to not implement that for now.
+            return new NativeArrayBuffer(0);
         }
 
         return new NativeArrayBuffer(JSType.toInt32(args[0]));