Integration with Feeds Module

I am trying to use Feeds module to create amazon item nodes (created by adding the ASIN cck field to a given node type). I have a csv file that lists amazon products with info such as Product Title, Manufacturer, ASIN. However, when I configure the importer to to map the fields form the csv file to the target fields in the amazon item, the ASIN field does not show up in the drop down. It appears that the Feeds module does not recognize the special ASIN cck field and cannot perform the mapping.

There is an API for the Feeds module that handles mapping to specialized content types and their fields. I just don't know the Amazon module and Feeds module well enough to utilize the API's. Below is the hook from the Feeds module that is supposed to handle the mapping.

/**
* Alter mapping targets for nodes. Use this hook to add additional target
* options to the mapping form of Node processors.
*
* For an example implementation, see mappers/content.inc
*
* @param &$targets
*  Array containing the targets to be offered to the user. Add to this array
*  to expose additional options. Remove from this array to suppress options.
*  Remove with caution.
* @param $content_type
*  The content type of the target node.
*/
function hook_feeds_node_processor_targets_alter(&$targets, $content_type) {
  $targets['my_node_field'] = array(
    'name' => t('My custom node field'),
    'description' => t('Description of what my custom node field does.'),
    'callback' => 'my_callback',
  );
}

I was wondering if anyone could somehow write a plugin for the amazon module that will expose the ASIN cck field to the Feeds module for mapping during csv import. Please let me know your thoughts on this, I am looking forward to hearing back.

Best,
-Bao