If no port monitor is running on the port, then the Sun system will not try to spawn a login. So, you have to remove any port monitor on the port. There is much disagreement over whether these EEPROM settings are required. They are not used once a port monitor is running. Just use them and it won't hurt anything.
Log in as root, type eeprom ttya-ignore-cd=true, and press Return.
This command means use HW carrier detect.
Type eeprom ttya-rts-dtr-off=true and press Return.
To reboot the system, type init 6 and press Return.
Is it critical to reboot now? No, but you'll need to reboot at some time.
Make sure the modem is properly connected and already programmed. Make sure the cable is OK. Your ...