Original post: [SOLVED, BUT DON'T SHUT THREAD FOR NOW] Boot loop after "apt-get upgrade"

Regret to ask again for the same prob, but my N900 isn't booting YET AGAIN because of the libXau problem which was once solved a month ago...
As original post suggested I disabled Extras-devel for better stability BUT forgot to equip backupmenu again... Then today I cleared some rootfs (in normal ways which proved to be OK before) did a normal "apt-get upgrade" and a lot of wares got updated and reboot and... stuck. Even before 5 white dots appear, the LED behaves like when you shut down and fades... Same phenomenon as previously met.
Now I decided to use the same method for this prob so I used the same flasher-3.5 command to boot into RescueOS, found here: N900 rescue OS - testing releasebut WTF it wasn't the same process from the beginning: stuck at a line:

"[6.392944] OMAP SSI hw driver loaded"

...and never went on for a bit. Tried changing Rescue OS image and won't work.

...
EDIT: Shoot, looks like the prob is simply an empty battery... Yes the same phenomenon as the libXau6 problem... Charged and everything's fine now.
Plus a tip: RescueOS won't boot (stuck at above lines) when battery's empty!

Anything requiring flashing won't work on very low battery. That line is for the modem driver, which, of course, requires considerable power to get up and running.

Have you upgraded libstdc++6?