My four yeas old Thinkpad T22 is acting up as far as battery is concerned. Windows XP Power meter shows a fully charged battery falls to 6% level within ten minutes and then it stays at that level for one hour. Clearly, BIOS is not supplying correct data. I have updated BIOS to latest version and reset defaults, drained battery fully a few times but nothing has worked so far. I know battery is not new but it can still feed power for more than an hour. How can I configure BIOS to supply right data?