Index: httpauth.module
===================================================================
--- httpauth.module	(.../vanilla/modules/httpauth/httpauth.module)	(revision 1510)
+++ httpauth.module	(.../extended/modules/httpauth/httpauth.module)	(revision 1516)
@@ -64,7 +64,8 @@
   }
   
   // Do what drupal_access_denied() would've done if we wouldn't've been called.
-  menu_set_active_item('');
+  print httpauth_access_denied();
+  exit();
 }
 
 /**
@@ -74,7 +75,17 @@
   $form['httpauth_status'] = array('#type' => 'checkbox', '#title' => t('Enable HTTP authentication.'), '#default_value' => variable_get('httpauth_status', FALSE), '#description' => t('<strong>Note:</strong> when you enable HTTP authentication, !the-setting will be modified. When you disable it again, the setting will be restored.', array('!the-setting' => l(t('the 403 (access denied) page setting'), 'admin/settings/error-reporting'))));
   
   $form['httpauth_pages'] = array('#type' => 'textarea', '#title' => t('Promote HTTP authentication on pages'), '#default_value' => variable_get('httpauth_pages', ''), '#description' => t('On which pages to promote HTTP authentication, if an anonymous user stumbles upon an access denied page. Enter one page per line as a Drupal path. The * character is a wildcard.'));
-  
+
+  // Pulled straight out of the error reporting form
+  $form['httpauth_site_403'] = array(
+    '#type' => 'textfield',
+    '#title' => t('Default 403 (access denied) page'),
+    '#default_value' => variable_get('httpauth_site_403', ''), 
+    '#size' => 40,
+    '#description' => t('This page is displayed when the requested document is denied to the current user. If unsure, specify nothing.'),
+    '#field_prefix' => url(NULL, NULL, NULL, TRUE) . (variable_get('clean_url', 0) ? '' : '?q=')
+  );
+
   $form = system_settings_form($form);
   $form['#submit'] = array($form['#base'] .'_submit' => array(), 'httpauth_settings_form_submit' => array());
   
@@ -202,3 +213,39 @@
     return explode(':', base64_decode($credentials));
   }
 }
+
+/**
+ * Rip-off of the function that does the access denied in Drupal itself
+ */
+function httpauth_access_denied() {
+  global $_menu;
+  drupal_set_header('HTTP/1.1 403 Forbidden');
+  watchdog('access denied', check_plain($_GET['q']), WATCHDOG_WARNING);
+
+  // Keep old path for reference
+  if (!isset($_REQUEST['destination'])) {
+    $_REQUEST['destination'] = $_GET['q'];
+  }
+
+  $path = drupal_get_normal_path(variable_get('httpauth_site_403', ''));
+  if ($path && $path != $_GET['q']) {
+    // Shouldn't need to do this because set_active_item should do it by default
+    // Clear the menu array so we can rebuild with the new path url
+    unset($_menu['items']);
+
+    menu_set_active_item($path);
+    $return = menu_execute_active_handler();
+  }
+  else {
+    // Redirect to a non-existent menu item to make possible tabs disappear.
+    menu_set_active_item('');
+  }
+
+  if (empty($return) || $return == MENU_NOT_FOUND || $return == MENU_ACCESS_DENIED) {
+    drupal_set_title(t('Access denied'));
+    menu_set_active_item('');
+    $return = t('You are not authorized to access this page.');
+  }
+  print theme('page', $return);
+}
+