I wanted to try out meego and installed uboot for powerkernel(v46).
After restarting i noticed that uboot finds the kernel, trys to boot and after trying to load the kernel the n900 restarts.
That's why i wanted to reflash the n900 with an fiasco image like i had done it several times before. But it doesn't work!!!
For getting the n900 into flashing mode I have to hold the ŽUŽ key while plugging it to the pc. But it just boots as it always does... no flashing mode
my linux-pc still recognizes the n900 (seen in the log-files) but the flasher is unable to find it.
No it is not Uboot problem.
It's your computer problem.
If you're using version 64bits of windows then you'll running into problem with this sort of thing.
i had exactly the same problem as you, with uboot stopping the phone from booting when installing the power kernel version. However I managed to get the flash working (Win 7 x64 with libusb fix).
ok...
now i've tried flashing under windows vista, ubuntu 10.10 32bit live-cd and opensuse 11.4 64bit and everytime the flasher couldn't find the n900 because it launched uboot and didn't turned into flashing mode...