I'm running a distribution based on Feather Linux 2.4.23. Running pppd consistently complains of serial loopback. (I've run pppd with the debug switch, and it seems to be receiving the same things it's sending out.) The modem is a Multitech USB CDMA wireless modem. Any insight or experience on how I can get serial loopback to stop on this thing?

Thanks in advance for any advice you can lend.