la mia stored

codice:
$stmt = odbc_prepare(odbc_pconnect('connc','user','psw'), 'CALL ORC552P(?, ?, ?, ?, ?, ?, ?, ?)');
$success = odbc_execute($stmt, array('R', '99', '40639', '000', '00000', '  ', '', ''));		
$Return = odbc_fetch_object($stmt);
var_dump($Return);

mi da questo

codice:
Warning:  odbc_fetch_object() [function.odbc-fetch-object]: No tuples available at this result index in D:\xampp\htdocs\function\update_cart.php on line 9
che vuol dire No tuples available ???