adsl plugin needs rp-pppoe to work otherwise you get these errors and the ADSL link doesn't come up
Jan 01 01:21:47 localhost NetworkManager[3128]: <info> Activation (eth1) starting connection 'pppoe-isp'
Jan 01 01:21:48 localhost NetworkManager[3128]: <warn> (eth1): PPPoE failed to start: Could not find pppoe binary.
Jan 01 01:21:48 localhost NetworkManager[3128]: <info> Disabling autoconnect for connection 'pppoe-isp'.
Jan 01 01:21:48 localhost NetworkManager[3128]: <warn> Activation (eth1) failed for connection 'pppoe-isp'