I tried this in ejabberd

badlop — Mon, 12 Jun 2017 10:29:54 +0000

I tried this in ejabberd 17.04:
login user1@localhost to the server, and join the room sala1@conference.localhost. Then I run this query:

$ ejabberdctl send_message groupchat user1@localhost/tka1 sala1@conference.localhost "" BoBo

And the room occupants receive the message.

ejabberd - Comments for "send message as user to another conference chat"