--- a/util/filters.lua	Wed Jun 02 12:23:07 2010 +0100
+++ b/util/filters.lua	Wed Jun 02 12:24:07 2010 +0100
@@ -46,6 +46,7 @@
 end
 
 function remove_filter(session, type, callback)
+	if not session.filters then return; end
 	local filter_list = session.filters[type];
 	if filter_list and filter_list[callback] then
 		for i=1, #filter_list do