Sinceramente in archivio ho trovato questo sorgente , ma nn ho avuto mai modo di testarlo.
penso che sui riferimenti devi aggiungere "faxcom 1.0 library", fai delle prove e vedi un po', cmq penso funzioni su linea analogica (modem56k).

codice:
Private Sub Form_Load()
    On Error GoTo ErrHandler
    Dim strComputer As String
    strComputer = "yourComputerName"
    Dim oFaxServer As FAXCOMLib.FaxServer
    Set oFaxServer = New FAXCOMLib.FaxServer
    Dim oFaxDoc As FAXCOMLib.FaxDoc
    oFaxServer.Connect strComputer
    oFaxServer.ServerCoverpage = 0
    Set oFaxDoc = oFaxServer.CreateDocument("c:\1.txt")


    With oFaxDoc
        .FaxNumber = "079919191"
        .DisplayName = "Fax Server"
        Dim lngSend As Long
        lngSend = .Send
    End With
    Set oFaxDoc = Nothing
    oFaxServer.Disconnect
    Set oFaxServer = Nothing
    Exit Sub
ErrHandler:
    MsgBox Err.Number & " " & Err.Description
End Sub
ps. fammi sapere come va'