Hmm I didnt think it was going to be a complicated issue, thought by bridging the ethernet and wlan on the Routerboard it will allow pppoe Requrests to go to the AP and get an answer from the AP direct,
the way the example is set for wds, i have to set an IP address on the Wlan but for PPPOE security it is written not to,
Actualy you can skip step 4 from WDS bridging How-to ( no need to set ip addresses ).
and if it is bridge how can i get the rest of the customers who have CPE's at there end to link up?
Customers with CPE's will act as before WDS setup ....
BTW, i use succefully as CPE Ovislink AirLive WL-1120 AP in WDS bridge mode against MT AP with WDS setup. This setup provide me with propper bridging for pppoe cleints. Ovislink AirLive WL-1120 AP are cheap realtek chipset based devices, but are feature rich, and never have need to be rebooted.