The following AddReg-type section must be added to your modem INF file so Windows Sockets will recognize the VoiceView transport.
Note also that this new AddReg section must be referenced in an AddReg= item in the Install section (see the topic Modifying the Install Section for an example of such an AddReg= item).
[VoiceView_Socket] HKLM, System\CurrentControlSet\Services\VxD\Winsock, "VoiceView Winsock Provider",, "wsvv.vxd"