I have a G-3 Ibook running OS 9.0 that, when it's running on external power
(not battary) remains asleep only every other time. That is, if I put it to
sleep after initial power up, it stays asleep. Then, after waking it and
putting it to sleep a second time, it wakes up within a few seconds. Then,
if I put it to sleep again, it stays asleep until awakened. This pattern
repeats indefinitely so that I have learned to wait around until it wakes
up by itself so that I can put it to sleep the second time. I've never been
able to understand this behavior.

Richard