iMac external modem dial-up issue with AOL

New iMac (OS X 10.4.7) + AOL 10.2.1 + External USB modem fails to
"detect carrier" (ie no dial tone)

Network Prefs can dial AOL using this device, but fails to connect due to a protocol
error I suspect (AOL is goofy in the link layer).

Attempting to dial using AOL, we get the sympton state. IMO, AOL is not seeing
the USB external modem even though the modem was connected when AOL was installed.

Anyone else seeing this?

Using the Network Config to dial another ISP provides access via the External USB Modem
and the Safari Browser runs nicely.

QED: AOL 10.2.1 for OS X is failing to find the modem.