There's no reason to ever run that much phone line, just put your modem by the phone jack in the wall, and run cat5 to your computer or lan from the modem. The 10' thing isn't nearly as important as the quality of the phone line, too. If it has had kinks in it, been stepped on a lot, etc., it seriously degrades performance. There's also stuff about running it paralel to in-wall electric cables. I don't remember. I didn't take it into consideration and I get all my 1.5,
Just take your modem, and find someplace close to the phone jack for it to live. That way your skinny phone cord is only a couple of feet long. My modem had phone-style hangers on the back, so it just hangs on the wall by the jack.
I've seen them run CAT5 a long way through office buildings, so I doubt 15 or 20 feet is going to be a problem for it.
