title: setting the value of a given cell in a jintArray
body: <p>I get the arr int[] from the JVM and want to set a value in it at a specified index,
  like this:</p>
  
  <pre><code>jintArray arr;
  jint* ints = _env-&gt;GetIntArrayElements(arr, false);
  int newvalue = 4;
  
  _env-&gt;SetIntArrayRegion(ints, 3, 1, &amp;newvalue); // this works
  inst[3] = newvalue; // this failed !!!
  </code></pre>
  
  <p>Can you tell me why the second assignment fails???
  It should work and be much faster (no method call).</p>
  
  <p>Thanks,
  Luc</p>