diff --git a/conf/metadata.php b/conf/metadata.php
index ff5023f..863b778 100755
--- a/conf/metadata.php
+++ b/conf/metadata.php
@@ -20,4 +20,4 @@
 
 $meta['autocollapse'] = array('onoff');
 $meta['closedwiki'] = array('onoff');
-$meta['copyright'] = [];
+$meta['copyright'] = array('');