NCM & device management via console server

Hi all,

I have quite a few devices that are managed via several Avocent console servers.  Telnet and SSH have been disabled, and the Avocent is the only access to the devices.  Is there a way to manage my devices via the console server in NCM? I've tried doing various configurations with the IP & the port numbers, but never have had success.  There is authentication at the console server and then authentication on the device itself.