The title says it all. It wakes up, but it doesn't connect to the Internet and applications don't respond. I fixed it for a little while by resetting the PRAM, but the problem has returned.
If you open a new user account, do the problems carry over? Also, have you tried reinstalling the latest version of your OS, the combo update? If you're running Tiger, then it's the 10.4.6 Combo Update.
It seems to be working fine again. I've already awaken my PowerBook two times since creating this thread and everything seems to be okay. If the problem persists, I'll try what you suggested. Thanks!