This bug fix is made of two parts:
1) It's now possible to dynamically add a camera.
2) Empty camera name on a SetCamera actuator now points to the actuator's parent object if this object is a camera.
This trick is useful to make current a dynamically created camera: just add a SetCamera actuator on the camera itself and leave the name empty. Later, when the camera is added in the scene with an AddObject actuator, either directly or via a parent object, you just need to activate the actuator to make the newly created camera current. If you set a name on a SetCamera actuator, it will always point to the original camera, even after replication.