Description:
------------
In object that implements ArrayAccess and accesses itself as array inside its own method, $this is not available ("Undefined variable: this")


Reproduce code:
---------------
<?php

class Foo implements ArrayAccess
{
	function offsetExists ($offset) {/*...*/}
 	function offsetGet ($offset) {/*...*/}
 	function offsetSet ($offset, $value) {/*...*/}
 	function offsetUnset ($offset) {/*...*/}

 	function fail()
 	{
	 	$this['blah'];
 	}

 	function succeed()
 	{
	 	$this;
	 	$this['blah'];
 	}

}

$bar = new Foo();
$bar->succeed();
$bar->fail();



Expected result:
----------------
No error. Both methods should work.

Actual result:
--------------
Notice: Undefined variable: this in c:\www\test.php5 on line 13