Description:
------------
total mishmash with casting and gettype

Reproduce code:
---------------
<?
 $v=(string)'';
 print('1. variable casted as string has type: '.gettype($v).'<br>');

 $v=(unicode)'';
 print('2. variable casted as unicode has type: '.gettype($v).'<br>');

 $v=(binary)'';
 print('3. variable casted as binary has type: '.gettype($v).'<br>');
?>

Expected result:
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I suggest:

1. variable casted as string has type: string (OLD PHP 5 behaviour, in PHP 6 for binary operation)
2. variable casted as unicode has type: unicode

Actual result:
--------------
1. variable casted as string has type: unicode
2. variable casted as unicode has type: unicode
3. variable casted as binary has type: string