The DC-In had been working intermittently. I replaced the laptop battery initially. Nothing. Then I replaced the charger. Again, nothing. I should've started by purchasing the $30 DC-in board from ifixit and that would've saved me a battery and a charger. Thatsolved the problem out right.
Followed ifixit guides and was extremely easy.
If your ibook's charger seems not to be working right, start by raplacing th DC-in board before you go through the expense of replacing batteries or chargers.