Using existing cable/VOIP modem for Voipo Possible?

Hello,

I have Cablevision's VOIP service (Optimum Voice), and I'm moving over to Voipo. Voipo sent me the adapter, so I plugged it into my router and it works fine - no issues so far. I notice a little hiss when calling home, but I can deal with that for the price.

Since I had Optimum voice, my cable modem already has two phone jacks. I was wondering if - instead of using another adapter - if I could setup my cable modem to use it's ports for the Voipo service.

I logged into the modem, and found a Telephony setup menu, which contained this:

MTA Reset to defaults (button)
Resetting the MTA to its factory default configuration will remove all stored parameters learned by the MTA during prior initializations. Configurations shall take into effect after reboot / reset MTA.

All other screens were simply a readout of connection statuses.

I looked up the modem online and found this spec:

Network Call Signaling (NCS) and Session Initiation Protocol (SIP) support

So, in theory, I should be able to set this up to support Voipo, but I'm not sure - even if I hit that reset button - that it's going to let me reprogram that feature without some special software that Cablevision uses.

Has anyone attempted this before? Got it to work?