I have a:
ibook 14.1/1.2ghzg4/256/60/combo/ap
MAC OS X-US
I've tried the resets suggested at the apple.com support site to no avail. The adapter shows that it is charging, and when I push the button on my battery only one light comes on, blinking. It's been plugged in long enough to be charged so I don't know what else to try.
I had a similar problem with my iBook. Although the adapter was plugged in the iBook wouldn't turn on. The adapter was broken, and even though it was lit I wasn't getting power. Head down to an Apple dealer and borrow an adapter to see if it powers your iBook. I think a new one is $50.