I’m currently not sure but I think since updating to 10.4.4 I have a strange problem: When I’m using my brand new powerbook for some time only on battery and it reaches something around 40%, power goes off without it simply falling into sleep mode. Today this happened to me two times. At least after the first occurance fully charging didn’t work either. The status froze at about 86% while the battery-indicator was green :-? I also checked if my battery is somehow affected by that battery exchange program but it isn’t, another reason for me to believe this to be more a problem on the software side. It’s also not as if the battery life time seems to be shorter than normal. Okay, I only tried it once to drain the battery completely (which was part of the battery calibration process) but this didn’t appear to me terribly longer. I’m also not really eager to try it again since it’s like a crash to the harddrive which I want to avoid.
Could this really be a flaw in MacOX 10.4.4? If it is, it’s in my opinion a quite severe one since it keeps the system from going into rescue-shutdown when the battery-charge (really) reaches zero.