To create a conference room you simply join a conference that doesn't exist, remember that the "server" is conference.domain.com (even if that doesn't exist in DNS).
If you had read the thread or looked at the bugs you would have seen that the conference / group chat is not available in the web client. Support for this is
Bug 31738 - Add ui for conference rooms (chat room).
Do you have a valid SRV record setup? If not are you manually specifying the server, port, and ssl settings correctly?