AT command set for datafire ISDN TA

I’m trying to get a datafire ISDN TA working with Linux (ISDN4Linux seems to recognize it ok, as I get a pile of ttyI* device files in /dev). However, in my foolishness I have lost the manual with the AT commands, and I can’t seem to find it online. The reason I need the manual is because I 'm getting a NO MSN/EAZ error when I try to send an ATD command to a number, and I know that it’ll be pretty easy to fix this when I know the actual AT command to change the setting that is causing this problem. Does anyone know where I’d find this manual?