--- admin.admin.inc	2009-11-16 16:28:35.000000000 +0100
+++ admin.admin.inc.new	2009-11-16 16:26:20.000000000 +0100
@@ -156,6 +156,22 @@ function admin_menu_overview_form_submit
 function admin_form_system_admin_theme_settings_alter(&$form) {
   // Add in our admin theme ('slate') as an option
   $form['admin_theme']['#options']['slate'] = t('Slate (formerly \'Admin\')');
+  
+  // allow the user to define a set of pages where the admin theme should or should not be applied to
+  // originall code goes in admin_theme module
+  $form['pages']['custom'] = array(
+    '#type' => 'fieldset',
+    '#title' => t('Custom pages'),
+    '#description' => t("Enter one page per line as Drupal paths. The '*' character is a wildcard. Example paths are %blog for the blog page and %blog-wildcard for every personal blog. %front is the front page.", array('%blog' => 'blog', '%blog-wildcard' => 'blog/*', '%front' => '<front>')),
+    '#collapsible' => TRUE,
+    '#collapsed' => TRUE,
+    '#weight' => 9,
+  );
+  $form['pages']['custom']['admin_path'] = array(
+    '#type' => 'textarea',
+    '#title' => t('Use administration theme on the following pages.'),
+    '#default_value' => variable_get('admin_path', ''),
+  );
 }
 
 /**