--- themekey_properties.module.org	2009-07-28 13:40:40.000000000 +0200
+++ themekey_properties.module	2009-07-28 13:40:12.000000000 +0200
@@ -130,6 +130,11 @@ function themekey_properties_themekey_pr
     'description' => t("System: Dummy - Dummy property. Value is allways 'dummy'"),
   );
 
+  $attributes['system:base_path'] = array(
+    'path' => 'system:base_path',
+    'description' => t("System: Base path - In case of a directory based multi-site setup the base path will be '/<directory>/', otherwise just '/'."),
+  );
+
   return array('attributes' => $attributes);
 }
 
@@ -178,6 +183,8 @@ function themekey_properties_themekey_gl
   $parameters['system:date'] = format_date(time(), 'custom', 'Y-m-d', 'default');
   $parameters['system:time'] = format_date(time(), 'custom', 'H:i:s', 'default');
 
+  $parameters['system:base_path'] = base_path();
+
   $parameters['system:dummy'] = 'dummy';
 
   return $parameters;