--- a/mod_archive_muc/mod_archive_muc.lua	Thu Nov 10 11:45:32 2011 +0100
+++ b/mod_archive_muc/mod_archive_muc.lua	Thu Nov 17 20:24:46 2011 +0500
@@ -17,6 +17,8 @@
 
 local AUTO_MUC_ARCHIVING_ENABLED = module:get_option_boolean("auto_muc_archiving_enabled", true);
 
+local NULL = {};
+
 module:add_feature("urn:xmpp:archive#preferences");
 module:add_feature("urn:xmpp:archive#management");