diff -r 907a52ed10e3 -r 8ceee38f5840 vm/src/test/java/org/apidesign/vm4brwsr/InstanceTest.java
--- a/vm/src/test/java/org/apidesign/vm4brwsr/InstanceTest.java	Sat Dec 01 10:35:24 2012 +0100
+++ b/vm/src/test/java/org/apidesign/vm4brwsr/InstanceTest.java	Sun Dec 02 21:00:12 2012 +0100
@@ -123,6 +123,14 @@
             Double.valueOf(0)
         );
     }
+
+    @Test public void jsObjectIsLikeJavaObject() throws Exception {
+        assertExec(
+            "JavaScript object is instance of Java Object",
+            Instance.class, "iofObjectZ",
+            Double.valueOf(1)
+        );
+    }
     
     protected String startCompilationWith() {
         return "org/apidesign/vm4brwsr/Instance";