Insert CCK node from PHP script

$node = new StdClass();
$node->title = "test3";
$node->type = 'clasificados';
$node->body = "booooooooody";
$node->status = 1;
$node->format = 1;
$node->moderate = 0;
$node->promote = 0;
$node->sticky = 0;
$node->revision = 0;
$node->field_contenido = array(0 => array('value' => 'no mas de 140 caracteres en este texto'));
$node->field_autor = array(0 => array ('value' => 'alguntwitter'));
$node = node_submit($node);
node_save($node);