Thanks Natch, just ordered tha Ac Adapter, i will receive it in the next four days. I hope that everything is as you described!
To tell the truth I haven't charged the item for more than 2 hours since when it has arrived (3 weeks ago). But if it is not the battery I can't do anything, I am from Italy (so no warranty) and I've bought the item from an Ebay seller that now seems to be a ghost...