Damn I´ve now the battery from my old 5800MX.
I connected the N900 with the PC by holding the "u"key. In the screen is a usb icon but the flasher don´t start to flash...
It is still say "Suitable USB device not found, waiting."

What do I wrong?

\\edit

IT WORKS but only on the computer (Win XP x86) of my girlfriend.
On my computer (Win 7 x64) the flashing doesn´t work.