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user can't join chat rooms

an admin or channel user may need to invite the new person to an xmpp channel. use gajim or pidgin to invite people.

if they still can't log in, it may be an issue with their client. (i have this issue on bitlbee with the 'pizzatalk' channel). they can try to leave the room, then invite themselves from pidgin, or have an admin invite them, then accept the invitation and join into that channel.