I had the same problem with a similar computer a while back. I think it was a PB 180c, but that's besides the point. In order to get the internal modem to work, I needed an Apple software package called 'Apple Telecom Software'. Go to thier swupdates web page and look for it. It should work, if it's an Apple modem in your machine (which it probably is). And I say that my little PowerBook is one of the most useful little machines I have in my house right now, wouldn't you agree?