Error on admin/content/node-type/[node-type] page

No, I'm not talking about node/add/son, I'm talking of admin/content/node-type/son.
I could delete the field since admin/content/node-type/son/fields was still reachable.

I've just tried for the 3rd time, with a new content-type, and I'm always getting that error: haven't you ever seen it?
If not, create a new content-type, eg. son, add a Node Reference from URL field to it, and then try to go to admin/content/node-type/son (the edit content-type form). I don't get the form showed. If you are getting it, I'll try with a Drupal fresh installation.

I'll try to look into the source code as soon as I have time to do it.

Greetings, Giovanni

I've tried with a fresh D6 installation, and it works fine.
Looking at the backtrace, I've found that maybe there's a conflict between this module and Vertical Tabs one.

If I disable VT, I can access again to the admin/content/node-type/[node-type] page.

Still according to the backtrace, the VT module runs vertical_tabs_form_alter(), vertical_tabs_node_type_form() and drupal_prepare_form(), then the control is passed to CCK.

I don't have time at the moment to look deeper at the VT source code. I'll check in the next days.

Giovanni

Here it is the code I think generates the error (from vertical_tabs.module):

function vertical_tabs_node_type_form($node_type) {
  module_load_include('inc', 'node', 'node.pages');

  // Build a psuedo-node for a sample node form.
  $node = (object) array(
    'type' => $node_type,
    'name' => '',
  );

  // Build a sample node form to find fieldsets.
  $node_form_state = array('values' => array());
  $node_form_id = $node_type .'_node_form';
  $args = array(
    $node_form_id,
    $node_form_state,
    $node
  );
  $node_form = call_user_func_array('drupal_retrieve_form', $args);
  $node_form['#post'] = $node_form_state['values'];
  drupal_prepare_form($node_form_id, $node_form, $node_form_state);
  ...