smartyの{section}関数に渡す配列は0から順番になってないと表示されない

{section name=key loop=$message}
 {$message[key]|escape}<br />
{/section}

$message = array('123','456','abc');

$o_smarty -> assign("message", $message);

$message[3] = '123';
$message[7] = '456';
$message[] = 'abc';

$o_smarty -> assign("emes", $emes);