Is there a way to modify the dial-in conferencing so that it doesn't require a leader to be present before a user can dial-in join? If there is no way to do this.. this would be a fantastic feature!
When you call the conference number it will ask you for the conference id. If there is such a conference id, you'll join that conference and if there isn't then a new conference will be created so others can join.
If we assume that the first one to create a conference is the leader, then a conference with no leader is a new one, which you still can dial and create(and become the leader). If this is not what you mean, please describe in more detail what you are trying to achieve.
I would like a user to be able to log into a conference ID where a leader is yet to be present. Some users tend to get to the conference before the leader has arrived. Other systems have something like a "participate code" when logging in.