Jabber public conference rooms

I’m pretty new to jabber, but I had a question about the conference rooms.

Basically, when I create them, they work great for users with my URL (userID@cubedwater.com), but they are inaccessible from other IDs, such as those hosted on gmail.com or jabber.org. Is this on purpose? I thought they were supposed to be public? (I allowed public searching for room).

Here is the exact message I get when trying from a jabber.org ID:

"The server “conference.jabber.cubedwater.com” has no conferencing services installed. Contact the administrator for more information. "