My activated and jailbroke 1.1.2 UK phone, after having worked flawlessly for a day, has the battery indicator stuck at about 90%, although connected to the computer and the symbol indicates it's charging. Any idea why that might be?

Also, connecting it to iTunes works only partially. Often I get an "unknown error 0xE8000001", and while the iPhone symbol appears on the left, the syncing breaks off with "the device has timed out", or even "the required disk could not be found", often crashing iTunes altogether.

I don't know if these two things are related in any way, but it looks like things are going quite the wrong way...