using hook_update to add a new cck field I am using d6.

I have a live site with an already built content type. I needed an extra column in the table, so I added this on install... I know realize how limiting this is and have rebuilt the content type to include this column as a field and I have unset the field in the form.

I have updated the code for this content type to include the new field, but when I move the code to my dev site, I do not see the new field.

Note: The content type was exported to code using the features module.

I thought maybe I need to run hook_update, but I haven't worked out how to do this.

This is what I have so far.

function mymoduel_update_6004(){
  #REF: http://drupal.org/node/1031548
  drupal_load('module', 'content');
  drupal_load('module', 'mymodule');
  content_notify('install', 'mymodule');
  content_notify('enable', 'mymodule');
  return array();
}


I run update.php... but no visible changes :(

Has anyone got any ideas how I can update my cck content types?
After hours of searching, I finally found a post by Drewish that solves this.

http://drewish.com/node/118

The key to this is letting drupal core know you want to create a new field instance using

content_field_instance_create()