try building with the latest gcc 3.x , not a gcc 4.x, they are different.
otherwise - use that old noisy 386 machine in the shed with your old linux, a network card and ip forwarding.
Better still throw the lucent card away and get a new modem.
I had one once, but the house took a direct lightning hit and fried the modem, so I got adsl. I can't say I miss the lucent modem.