ppp conection with cell phone as a server

["Listas" <listas@kernelinformatica.com.br>]

Hi guys, I need to configure a ppp server with cell phone as my modem. I got
one Nokia 6120 and a serial data cable and connected it on my Linux box
runing mgetty with autoppp(I tested it with serial external modem and its
running ok). I tested the serial conection between my cell phone and my
linux box with minicom, and its ok too. I configured my cell phone to answer
calling and its ok. But when I try to make one connection between a Windows
dialup client to my linux I got this error: failed in mg_init_data. I didnt
found information about this kind of conection, Anyone here can help me with
some informations?

tks