Description:
------------
PDO_FETCH_FUNC doesn't know the uppcase function name.


Reproduce code:
---------------
<?php
$x = new PDO("sqlite::memory:");
$x->query("create table test(name string, value string)");
$stmt = $x->prepare("INSERT INTO test (NAME, VALUE) VALUES (:name, :value)");

$stmt->bindParam(":name", $the_name, PDO_PARAM_STR, 32);
$stmt->bindParam(":value", $the_value, PDO_PARAM_STR, 32);

for ($i = 0; $i < 4; $i++) {
	$the_name = "foo" . rand();
	$the_value = "bar" . rand();

	if (!$stmt->execute()) {
		break;
	}
}

$stmt = $x->query("SELECT * FROM test");

function toXML($foo, $bar) {
	return "<name>$foo</name><value>$bar</value>";
}
print_r($stmt->fetchAll(PDO_FETCH_FUNC, 'toXML')); // not work
print_r($stmt->fetchAll(PDO_FETCH_FUNC, 'toXML')); // work fine
?>

Expected result:
----------------
Array
(
    [0] => <name>foo2052</name><value>bar20973</value>
    [1] => <name>foo18466</name><value>bar17075</value>
    [2] => <name>foo8304</name><value>bar8169</value>
    [3] => <name>foo17518</name><value>bar22287</value>
)

Actual result:
--------------
C:\php-5.0.5>php pdo.php
PHP Warning:  PDOStatement::fetchAll(): SQLSTATE[HY000]: General error: user-supplied function does not exist in C:\php-5.0.5\pdo.php on line 26

Warning: PDOStatement::fetchAll(): SQLSTATE[HY000]: General error: user-supplied function does not exist in C:\php-5.0.5\pdo.php on line 26
PHP Warning:  PDOStatement::fetchAll(): SQLSTATE[HY000]: General error: user-supplied function does not exist in C:\php-5.0.5\pdo.php on line 26

Warning: PDOStatement::fetchAll(): SQLSTATE[HY000]: General error: user-supplied function does not exist in C:\php-5.0.5\pdo.php on line 26
Array
(
)