Access to the associative array index in Smarty

<?php
$users = array();

$users[1] = array('fname' => 'John', 'lname' => 'Smith');

$users[2] = array('fname' => 'James', 'lname' => 'Bond');

$ids = array();

$ids[] = array('uid' => 1);

$ids[] = array('uid' => 2);

$smarty->assign('users', $users);

$smarty->assign('ids', $ids);

?>

{foreach item=user from=$ids}

    {$users[$user.uid].fname} {$users[$user.uid].lname}

{/foreach}

or

{foreach item=user from=$ids}

    {assign var=u_id value=$user.uid}

    {$users.$u_id.fname} {$users.$u_id.lname}

{/foreach}