diff --git a/main/inc/lib/fckeditor/editor/plugins/ajaxfilemanager/inc/config.base.php b/main/inc/lib/fckeditor/editor/plugins/ajaxfilemanager/inc/config.base.php
index 7e2b984598..5fe8bb271f 100644
--- a/main/inc/lib/fckeditor/editor/plugins/ajaxfilemanager/inc/config.base.php
+++ b/main/inc/lib/fckeditor/editor/plugins/ajaxfilemanager/inc/config.base.php
@@ -170,8 +170,17 @@
 		 * 		
 		 */
 		
+	// Modified by Ivan Tcholakov.
+	//define('CONFIG_WEBSITE_DOCUMENT_ROOT', '');
+	if (preg_match('@'.api_get_path(REL_PATH).'$@', api_get_path(SYS_PATH))) // Sanity check.
+	{
+		define('CONFIG_WEBSITE_DOCUMENT_ROOT', preg_replace('@'.api_get_path(REL_PATH).'$@', '', api_get_path(SYS_PATH)));
+	}
+	else
+	{
+		define('CONFIG_WEBSITE_DOCUMENT_ROOT', ''); // Let the ajaxfilemanager try alone to find the document root.
+	}
 
-	define('CONFIG_WEBSITE_DOCUMENT_ROOT', '');	
 	//theme related setting
 			/*
 			*	options avaialbe for CONFIG_EDITOR_NAME are:
@@ -192,4 +201,4 @@
 	//$langdokajax= api_get_language_isocode(); //from dokeos. return, en, es... 
 	define('CONFIG_LANG_INDEX', 'language'); //the index in the session
 	define('CONFIG_LANG_DEFAULT', (CONFIG_QUERY_STRING_ENABLE && !empty($_GET['language']) && file_exists(DIR_LANG . secureFileName($_GET['language']) . '.php')?secureFileName($_GET['language']):'en')); //change it to be your language file base name, such en
-?>
\ No newline at end of file
+?>