Indy TIdFTP and Modemconnection

I have a small problem with WIN2000/Prof. I wrote a small appication that
only appends a textfile. The application is working, but I have to make the
connection to the network manuell. If I use this app with WIN98, so will
automaticly raise a dialog to make the connection.
Do somebody know how I can tell Windows to raise this dialog?
Many Thanks
Uwe