Meetme list cmd can't work

before when i use meetme list cmd ,the asterisk will show the list of all active conference. but now it shows me the usage. i don’t know what’s wrong .and when i use ‘meetme list 1000’ cmd asterisk show me ‘1 users in that conference’ but i remember it should show the use list in the conference . what’s wrong ?i remember i do nothing with asterisk.i just debug some php agi script . anyone meet such a issue? any reply would be greate appreciated!

any ideas?