The only thing you need to do to use Socket Communications' CompactFlash Digital Phone Card for Sprint PCS Touchpoint 120 with a Linux PC laptop or Sharp's SL-5000D 'Zaurus' Linux/Java PDA is to set the baudrate to 4800. For a laptop, all you need is to get a CF-to-PCMCIA converter. On Zaurus currently you need to manually edit the dialup file in /home/etc/ppp/peers/ after setting up phone number etc. and change whatever baudrate (the first line) to 4800.