[CentOS] [OT] VOIP

Hello,

I changed ISPs a few weeks ago and now I'm on cable.  In doing so, I lost
the ability to use the DSL as a FAX line.

So, I bought an OOMA. Turns out it uses a number of ports, three of which
are reserved, 53 TCP/UDP, 110 TCP and 443 TCP. These ports have already been
port forwarded from my cable modem/router to my server.

I'm thinking this isn't going to work unless I change some ports on my
server, which I'm not willing to do.

I spent over 30 minutes with their support people last night. It appears the
ports cannot be changed on the OOMA device.

Are there any work arounds?

TIA