"Connection Reset By Peer" on ssh sessions

[Fred]

I've got an annoying problem with the new Verizon Fios service.

If I leave an ssh session open and sits idle for longer than 2-5 minutes, it 
is killed with a "Connection Reset by Peer" error message.

This is *extremely* consistent as I usually keep quite a few sessions open 
for monitoring and maintenance, etc.

I've checked everything, including the PPPoE timeout setting on the router. 
I've checked the ssh_config on the client side and the sshd_config on the 
server side. No timeouts.

I've noticed this happening with other TCP/IP sessions, most notably IMAP 
sessions that stay idle for too long.

So, the finger seems to strongly point towards Verizon Fios.

I've called them about this, and although the techs were extremely eager to 
remedy this problem, they had no clue about it either.

I *suspect* that the Verizon engineers must've configured their equipment to 
do an idle timeout at the individual TCP/IP connection level, but failed to 
tell their support staff about it. And yes, I did get a tech there I could 
speak straight network jargon with without the annoying "it's not in my 
(customer service) script" reaction.

Any suggestions before I pull my hair out?

-Fred