Description:
------------
Hello,
While trying to connect to Oracle database with PDO_OCI, i get ORA error following : 

ORA-12533:TNS:illegal ADDRESS parameters

If i modify the TNS identifier in the source code (index dbname of $params array) nothing change, even if the tns i use doesn't exist. With Oracle software, it works, it will work also with oci8 package

Reproduce code:
---------------
$options = array ( Zend_Db::CASE_FOLDING => Zend_Db::CASE_UPPER);
$params = array ('username' => 'myuser', 
		'password' => 'mypass',
		'dbname'      => 'TEST1_SFSORAA1',
		'options'  => $options);
try{			
  $db = Zend_Db::factory("PDO_OCI",$params);
  $db->getConnection();
  return $db;
}catch(Zend_Db_Adapter_Exception $e){
	echo $e->getMessage();
}

Expected result:
----------------
successfull logon

Actual result:
--------------
logon faailure due to TNS problem