Problem while dial up with Linux Open Suse 10.2 and Nokia 2116

since i can set up my Linux Open Suse to dial up from Nokia 2116, i often found my modem is hang up by it's self. I guess the problem is because the modem (nokia 2116) become hot when i use to connect to internet. What i do next is i put my modem near to my fan and the modem never hang up and my connection run well :)