Its probably not the modem type, but the firmware version. You need v1.0
(or higher) at the client modem to successfully connect in the 56K mode
with the PortMaster 3. Please contact your client modem vendor and urge
them for the v1.0 flash update (Supra has the v1.0 release on their web in
the BETA test section). If you don't know what client modem version level
you are operating with see
http://www.livingston.com/Marketing/Products/56Krules.shtml for more details.
-- Marty Likier Product Marketing Mgr. marty@livingston.com