diff -r 59d5596a9c6c -r ae352b763959 vm/src/test/java/org/apidesign/vm4brwsr/ClassTest.java
--- a/vm/src/test/java/org/apidesign/vm4brwsr/ClassTest.java	Mon Feb 11 12:46:43 2013 +0100
+++ b/vm/src/test/java/org/apidesign/vm4brwsr/ClassTest.java	Fri Feb 15 21:14:49 2013 +0100
@@ -196,5 +196,11 @@
     ) throws Exception {
         code.assertExec(msg, clazz, method, expRes, args);
     }
+    @Test public void isClassAssignable() throws Exception {
+        assertExec("isAssignable works on subclasses", Classes.class, 
+            "isClassAssignable__Z", 
+            true
+        );
+    }
     
 }