Cannot create biblio nodes with drupal_execute('biblio_node_form',...)

I noticed when debugging that selecting 'Web Article' (or presumably anything) from the drop down box calls nodeapi($node->type='biblio', $op='validate') with $node->op='Populate using DOI'

I tried getting aroudn this but could not.

When I have a missing required field I get the appropriate form validation errors from the biblio node. However, when I fill in those fields, only the $op=validate is getting called, with no raised errors.

function auto_biblio_entry_nodeapi(&$node, $op, $a3 = NULL, $a4 = NULL){

	if($node->type == 'biblio' && $op == 'validate'){
	//	print "validating biblio:<br /><pre>"; print_r($node); print "</pre>";
	}
	if( $op == 'insert' &&  in_array($node->type, variable_get('auto_biblio_entry_types', array() ) ) ){

		global $base_url;
		$bib_node = array(
			'uid' => (string) $node->uid,
			'name' => (string) $user->name, 
      'type' => 'biblio', 
      'language' => '', 
      'body' => NULL, 
      'title' => $node->title, 
      'format' => NULL, 
      'status' => true, 
      'promote' => false, 
      'sticky' => false, 
      'created' => time(), 
      'revision' => false, 
      'comment' => '0', 
      );
     $bib_node = (object) $bib_node;
	//	$bib_node->uid = $node->uid;
	  module_load_include('inc', 'node', 'node.pages');
	  
	  
		$values = array();
	//	$values['op'] = t('Populate using DOI');
		$values['biblio_type'] = "107";
		$values['title'] = $node->title;
		$form_state = array();
		
		$values['biblio_year'] = date('Y', $node->created);
		$form_state['values'] = $values;
	
	//	drupal_execute('biblio_node_form', $form_state, $bib_node);
		$x = 0;
		foreach($node->field_author_reference as $author){
		dpm($x . " time through");
			$values['biblio_contributors'] = array(
				'1' => array(
					"$x" => array(
						'name' => _auto_biblio_entry_author_name($author['uid']),
						'auth_type' => 1,
						'cid' => null,
						'rank' => $x,
						),
					),
				);
				$x = $x + 1;
		}
		$values['biblio_publisher'] = "Solutions";
	  $values['biblio_type'] = "107";
		$values['biblio_abst_e'] = $node->field_abstract[0]['value'];
		$values['biblio_url'] = $base_url . '/node/' . $node->nid;
		$values['biblio_type_name'] = t('Web Article');
		$values['name'] = $node->name;
		

	/*	$values['doi_data'];
		$values['paste_data']; */
		$values['op'] = t('Save');
		
		$form_state = array();
		$form_state['values'] = $values;
		drupal_set_message("creating bib after feat");
		dpm($form_state);
		drupal_execute('biblio_node_form', $form_state, $bib_node);
		$errors = form_get_errors();
		dpm($errors);
		if (count($errors)){
			drupal_set_message("A biblio node may not have been created");
		}
	}
}