VB1 & Internal Modem

We are in the process of trying to install a new communications program which was written in VB1. We have been told by the person that wrote the program that VB1 has a conflict with most internal modem drivers and we must install an external US Robotics modem (and another serial port since we have none open). I'm guessing there is a way to get our internal Hayes compatible modem to work, but I'm not sure where to start.

Thanks in advance for any and all assistance.

I would be more afraid of the dll hell that installation is likely to cause you.