Having problems working with the API

Hello,

I have 2 content types: "quote" and "contract". Both have the same fields: "field_node_state" (a select box) and "field_products" (a node-reference field).

I'm trying to convert quote nodes into contracts, via my custom module, but I'm having problems with the node_convert API. I'm not sure what I'm doing wrong. Here's a code snippet:

<?php
if (module_exists('node_convert')) {
  node_convert_node_convert($data->nid, 'contract', array('field_node_state', 'field_products'), array('field_node_state', 'field_products'), TRUE);
}
?>

Am I supposed to include the "title" and "body" fields in the $source_fields and $dest_fields arrays, along with the "field_x" fields? The documentation says these variables should be "an array containing the source field names" and "an array containing the destination field names", but it doesn't specify whether or not "title" and "body" should be included.

Also, I'm not clear on what I'm supposed to do with the $hook_options parameter. This is optional, correct?

Thank you.