сабж

В документации написано, что это невозможно, возможна шифрация только по WEP.

LAN-type WDS
This is the easiest, and currently most common, type of WDS used for linking LANs. It is very simple to setup and requires no extra routing protocols or knowlage of networking. Simply put, it is pure bridging. A simple example would be extending the range of an existing AP by setting up a 2nd AP and connecting it to the first using LAN-type WDS. To do this, first make sure you are not using any type of Wireless security (WEP/WPA).