Begining in ROS 6.33 the PPPoE server can forward the PPPoE circuit-id received from the NAS to the Radius server using the NAS-Port-Id attribute.
/ppp aaa set use-circuit-id-in-nas-port-id=yes
It would be very nice to see the circuit-id in a new column in the PPP / Active Connections tab in WinBox.
Thanks!