since I got my jasjar I I saw,sometimes, the battery was drained at 50% without using my jasjar in 3 or 4 hours. only one or two short phone calls. no msn running or any application. I have written a little C program that writes to a log file each 10 seconds the actual time(hour, minute and second) . ok, if there isn't 3g connection (of course, no programs running), and I turned off the device and when I turn on the device 5 minutes later I could see the CPU hasn't been running, so minimal battery drain. But if I do the same test but connected to UMTS (again no programs running, only the test program) I could see that my test program many times continues working many minutes, so cpu is working (i turned off the device), then it stops few seconfs, again It continues working....(the screen was turned off). so......be carefull if you turn off your jasjar with the umts connection active. while you think that your device is turned off and you are saving battery......its possible the cpu is running eating the battery.