hub 8-0:1.0: over-current change on port 1

hub 8-0:1.0: over-current change on port 1
hub 2-0:1.0: over-current change on port 5

I don't know what does that means, but my dmesg is FULL of those!
Please see the following post on ubuntuforums:

http://ubuntuforums.org/showthread.php?t=1691226

I don't know if it helps, but there is a malfunctioning USB port on my laptop. Pluggion an optical mouse into it, the port gives current to the mouse but the mouse does not work. In fact, the mouse has some lights which blink when it is plugged into the mulfunctioning port and also the mouse pointer does not moves on the screen when the mouse is moved on my mouse pad.
On the other hand, when plugging the mouse into a functioning USB port, the lights do not blink any more (they just blink when the mouse is moved on my mouse pad) and moving the mouse on my mousepad makes the mouse pointer regularry move on the screen.

In case of inserting a USB Flash drive into the malfunctioning port I can get the following error message:
Error mounting: mount: /dev/sdc1: can't read superblock

or even no error message. In this last case, the flash memory can be not mounted at all or mounted for a while and then unmounted as when suddenly unplugged. Of course, the flesh memory works perfectly when plugging it into other usb ports of the same laptop.

Any suggestion, pls?
Thanks.

Manolo

Ubuntu 10.10 on Acer Aspire 5730z