diff -r b157a354003f -r 4252bfc396fc vmtest/src/test/java/org/apidesign/bck2brwsr/tck/CompareByteArrayTest.java
--- a/vmtest/src/test/java/org/apidesign/bck2brwsr/tck/CompareByteArrayTest.java	Tue Jan 15 12:38:49 2013 +0100
+++ b/vmtest/src/test/java/org/apidesign/bck2brwsr/tck/CompareByteArrayTest.java	Tue Feb 26 14:55:55 2013 +0100
@@ -61,10 +61,22 @@
         return atIndex(-1);
     }
 
+    @Compare public String toOfBounds() {
+        return toIndex(5);
+    }
+
+    @Compare public String toOfBoundsMinus() {
+        return toIndex(-1);
+    }
+
     private static final int[] arr = { 0, 1, 2 };
     public static String atIndex(int at) {
         return "at@" + arr[at];
     }
+    public static String toIndex(int at) {
+        arr[at] = 10;
+        return "ok";
+    }
     
     
     @Factory