Description:
------------
Pdo do not bindParam?s
if bindParams is used and after that execute returns false for any cases?!?

Reproduce code:
---------------
public function getAll($amount = null, $offset = null)
	{
		$limit = null;
		
		if ($amount !== null)
		{
			$limit = "LIMIT ".(int)$amount;

			if ($offset !== null)
			{
				$limit = "LIMIT ".(int)$offset.", ".(int)$amount;
			}
		}
		
		$stmt = $this->prepare("SELECT * FROM contents :LIMIT");
                $stmt->bindParam(':LIMIT' => $limit);
		$stmt->execute();
		$ret = array();
		
		while($row = $stmt->fetchObject('some class'))
		{
		    $ret[] = $row;
		}
		
		return $ret;
	}