Why are myarray instanceof Array and myarray.constructor === Array both false when myarray is in a frame?
<p>So the following code alerts false twice:</p>

<pre><code>window.onload = function(){
                    alert(window.myframe.myarray instanceof Array);
                    alert(window.myframe.myarray.constructor === Array);
                }
</code></pre>

<p>When there's an iframe in the page named "myframe" that has contains an array called "myarray". If the array is moved into the main page (as opposed to the iframe), then the code alerts true twice as expected. Does anyone know why this is?</p>
