well access concentrator is just server on the LAN which is offering PPPOE services. So there can be many on the LAN , and you need to select one. SO....

After you install rp-pppoe-3.8 , run the following command, "/sbin/pppoe -A "

You will get a list of access concentrators and services on the command prompt., then make a note which one is yours.... Then , instead of "go-gui" ..just run "go" from the rp-pppoe directory, this will start the PPPOE dialer from command prompt without the GUI..

Also , if you need more assistance , you can give me a call, contact me off the list.