Make what is called a ``direct'' entry in your /etc/remote file (see remote(5)). For example, if your modem is hooked up to the first serial port, /dev/cuaa0, then put in the following line:
Use the highest bps rate your modem supports in the br capability. Then, type tip cuaa0 (see tip(1)) and you will be connected to your modem.
If there is no /dev/cuaa0 on your system, do this:
# cd /dev # sh MAKEDEV cuaa0
Or use cu as root with the following command:
# cu -lline -sspeed
with line being the serial port (e.g. /dev/cuaa0) and speed being the speed (e.g.57600). When you are done entering the AT commands hit ~. to exit.