Description:
------------
I am trying to set a default fetch mode using the PDO::ATTR_DEFAULT_FETCH_MODE as mentioned on http://www.php.net/pdo. Trying to do this results in the error:

Undefined class constant 'ATTR_DEFAULT_FETCH_MODE'

Hopefully my code is correct. ;)

Reproduce code:
---------------
$pdo = new PDO('mysql:host=host;dbname=db', 'user', 'password', array(
    PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC
));

Expected result:
----------------
I expect the code to connect to the mysql database and set FETCH_ASSOC as the default fetch mode.

Actual result:
--------------
Fatal error: Undefined class constant 'ATTR_DEFAULT_FETCH_MODE' in /path/to/my/script.php on line...