I'd like to suggest a feature I see on other conferencing products that would be so helpful on Uberconference. When a conference is locked or, better yet, whenever the conference is placed in a "put new participants in the waiting room until invited in" mode, uberconference would:
1. Audio - the caller would be told that the conference organizer has requested that all new participants wait in the waiting room until added to the conference by the organizer. While in the waiting room, the caller can press some number to "knock" to let the organizer know they are there.
2. Visually/on the web/app - the caller would be placed in a waiting room that is obvious from the user interface. If the caller is in the waiting room he can click to "knock" or even leave a tex message for the organizer. When the organizer lets them in, they would see the usual interface. The organizer would see the people in the waiting room as a separate section in the usual interface and can add them/let them in by clicking on them/confirming their admission.