What are your distances like? I've successfuly run 350s over crappy (I mean real crappy, full of splices, etc) old POTS-grade lines up to 440 feet. You might be able to get further with quality Cat 5, or better, cable. You might have to step down the speed and/or duplex of the Ethernet ports on both sides to get it to work. Between 440 and 500 feet, I can still show a link light, but can't pass layer 3 data, haven't tested further to find out why; could be attenutation on the wire, in which case maybe running larger gauge wire would help.