Yesterday I started iBooks on my ipad2 3g 64 latest OS. unfortunately the bookshelves were empty and after 2 seconds it crashed to black and then back to home page. This happened on each occasion I started it. I pluded into into iTunes (latest version) and my books folder showed empty. Today I restored the system (5 hours ) but it's more or less the same except now the books show for 2 mins and then goes to black and then homepage. Whats happened. I've looked thru' the previous but don't fine this problem