diff --git a/lib/plugins/acl/admin.php b/lib/plugins/acl/admin.php
index 4299ab220c270808ea4999b3e461b272c5de57ce..172c13af3477cabdb4a6a61ab95ad39cdc9ba5e8 100644
--- a/lib/plugins/acl/admin.php
+++ b/lib/plugins/acl/admin.php
@@ -5,7 +5,9 @@
  * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
  * @author     Frank Schubert <frank@schokilade.de>
  */
-if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../../').'/');
+// must be run within Dokuwiki
+if(!defined('DOKU_INC')) die();
+
 if(!defined('DOKU_PLUGIN')) define('DOKU_PLUGIN',DOKU_INC.'lib/plugins/');
 require_once(DOKU_PLUGIN.'admin.php');
 
diff --git a/lib/plugins/admin.php b/lib/plugins/admin.php
index 480fc07dd4b3c28ea495d58ea27bf1557fa731a9..7245a73eb26b0bf5110bdd13eb6048205df035ea 100644
--- a/lib/plugins/admin.php
+++ b/lib/plugins/admin.php
@@ -5,7 +5,9 @@
  * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
  * @author     Christopher Smith <chris@jalakai.co.uk>
  */
-if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../../').'/');
+// must be run within Dokuwiki
+if(!defined('DOKU_INC')) die();
+
 if(!defined('DOKU_PLUGIN')) define('DOKU_PLUGIN',DOKU_INC.'lib/plugins/');
 
 /**
diff --git a/lib/plugins/config/admin.php b/lib/plugins/config/admin.php
index d98ae3ffdd0d44169fc2381fe9c4a3a50bc7c316..8031b6f278e18a33a82a904eb34bcbb2e1770496 100644
--- a/lib/plugins/config/admin.php
+++ b/lib/plugins/config/admin.php
@@ -5,8 +5,9 @@
  * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
  * @author     Christopher Smith <chris@jalakai.co.uk>
  */
+// must be run within Dokuwiki
+if(!defined('DOKU_INC')) die();
 
-if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../../').'/');
 if(!defined('DOKU_PLUGIN')) define('DOKU_PLUGIN',DOKU_INC.'lib/plugins/');
 require_once(DOKU_PLUGIN.'admin.php');
 
diff --git a/lib/plugins/info/syntax.php b/lib/plugins/info/syntax.php
index d5209397f04d2f7bde979c4c1b8558cde494c41e..b93ef4887de3da60362bff4f49239bc0427c34f3 100644
--- a/lib/plugins/info/syntax.php
+++ b/lib/plugins/info/syntax.php
@@ -5,9 +5,9 @@
  * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
  * @author     Andreas Gohr <andi@splitbrain.org>
  */
+// must be run within Dokuwiki
+if(!defined('DOKU_INC')) die();
 
-
-if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../../').'/');
 if(!defined('DOKU_PLUGIN')) define('DOKU_PLUGIN',DOKU_INC.'lib/plugins/');
 require_once(DOKU_PLUGIN.'syntax.php');
 
diff --git a/lib/plugins/plugin/admin.php b/lib/plugins/plugin/admin.php
index 26f796162387655506f3fc37c8867fe1d8a87ba0..2ea63f45bcc9464e52b940fd9d9499cb6843fb17 100644
--- a/lib/plugins/plugin/admin.php
+++ b/lib/plugins/plugin/admin.php
@@ -5,13 +5,14 @@
  * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
  * @author     Christopher Smith <chris@jalakai.co.uk>
  */
+// must be run within Dokuwiki
+if(!defined('DOKU_INC')) die();
 
 // todo
 // - maintain a history of file modified
 // - allow a plugin to contain extras to be copied to the current template (extra/tpl/)
 // - to images (lib/images/) [ not needed, should go in lib/plugin/images/ ]
 
-if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../../').'/');
 if(!defined('DOKU_PLUGIN')) define('DOKU_PLUGIN',DOKU_INC.'lib/plugins/');
 require_once(DOKU_PLUGIN.'admin.php');
 
diff --git a/lib/plugins/syntax.php b/lib/plugins/syntax.php
index 9918e552a30fe0abfa1ea1032103ea1d404d3f4d..e5e6204c467f1331d15e2245ec8e3d7a68d940ae 100644
--- a/lib/plugins/syntax.php
+++ b/lib/plugins/syntax.php
@@ -5,8 +5,9 @@
  * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
  * @author     Andreas Gohr <andi@splitbrain.org>
  */
+// must be run within Dokuwiki
+if(!defined('DOKU_INC')) die();
 
-if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../').'/');
 if(!defined('DOKU_PLUGIN')) define('DOKU_PLUGIN',DOKU_INC.'lib/plugins/');
 require_once(DOKU_INC.'inc/parser/parser.php');
 
diff --git a/lib/plugins/usermanager/admin.php b/lib/plugins/usermanager/admin.php
index 1c3443af1dc837d0f616dfd448138f7d7b5f503a..07be2a905847c722448d5e58398ff14829f1a860 100644
--- a/lib/plugins/usermanager/admin.php
+++ b/lib/plugins/usermanager/admin.php
@@ -10,7 +10,9 @@
  *  @author  neolao <neolao@neolao.com>
  *  @author  Chris Smith <chris@jalakai.co.uk>
  */
-if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../../../').'/');
+// must be run within Dokuwiki
+if(!defined('DOKU_INC')) die();
+
 if(!defined('DOKU_PLUGIN')) define('DOKU_PLUGIN',DOKU_INC.'lib/plugins/');
 if(!defined('DOKU_PLUGIN_IMAGES')) define('DOKU_PLUGIN_IMAGES',DOKU_BASE.'lib/plugins/usermanager/images/');
 require_once(DOKU_PLUGIN.'admin.php');