Claire,
I have had successful modem connections of 9600 and 14400 through the QTelNet line of FXS and FXO’s. We were able to go out of an external modem on a computer, into an FXS port, dial the “alias” of the other unit ( in your case it would be set up in a hotline scenario, i.e. as soon as the unit goes off-hook, the call is sent directly to the FXO ) and connect at the mentioned speeds with very good success. Check out:
http://www.qtelnet.com or contact me and I will be able to assist you in finding out more about the appplication at:
gary@loookieloo.net
Gary.