This paper reports about the recent advances towards establishing a common platform for adaptive educational hypermedia (AEH) authoring. We present the conversion from MOT, a dedicated authoring system, to AHA! used in this context as delivery system for AEH. Moreover, we describe two new representation languages that emerged in the process: a common format for defining the static material, CAF, and an extended adaptation language for the description of the dynamic behaviour, LAG. Finally, some evaluations are shown and conclusions are drawn