so no magic in that. one can't sync often enough!

so simplified its like this:

a) reinstall the maemo kernel(to inform the system it will be there again)
b) now the system thinks it is installed but it isn't so you flash the kernel. with something like flasher --local -f -k kernelwhereever_it_is
c) that flashes the kernel to the nand so everything is fine and you reboot to actually run it with your new(old) kernel.

that would be roughly the same i do, only that i use the flasher on the pc.
thanks a lot!