Orcon NF4V router - no telnet option, and using vanilla firmware

Hi

I just had a new DSL connection set up with Orcon, and they've sent me their Orcon branded Netcomm NF4V router.

I want to extract the Orcon Genius password from the router, but to do so I need Telnet access into the router.

It looks like Orcon have disabled this option, as there is no telnet option under Services in Access Control.

I understand Orcon don't supply this password as it contravenes their T&C.

Does anyone know if I can update to the vanilla Netcomm firmware, and not lose the password information in the process?

Cheers