Richard Lewis has installed a Lucent Venus modem which Linux appears to regognise a emulating a serial port, but kppp does not recognise as a modem.
Richard, I am not sure sure what you mean by a "hardware" modem in this context.
What kppp is probably expecting is a modem that responds to the Hayes command set, i.e. kppp can send 'AT' style commands to the serial port the modem is on in order to make it dial, hangup etc. An external modem contains a microprocesser "the controller" to look after this side of operation.
I wonder if, in this context, "hardware" means it's an HCF modem, i.e. the card contains a DSP chip to do the hard work, but still needs software on the PC to perform the "controller" function. I would go back to linmodems.org to see if there is a driver listed for it.
Steve.