Sportster 28,800 fax driver

I have a USR sporster 28.800 fax modem.
Until 2 days ago this worked fine, and I have made no system changes.
During the handshake, speed negotiation phase, my modem is hanging up but my software still sees me in the dialing phase. I have made all possible changes as recommended by my ISP to no avail. I have compared my tcp/ip settings, etc. to those on my laptop which connects okay.

My isp recommends I update the driver for this modem, but 3com/usr does not have a driver available at their website.

any suggestions on config settings or finding a current driver would be greatly appreciated.