Except that the errors are not multiples of an hour. And it "should" be fine but it's not ... that's why it's a problem. The clock does not need wifi or 3G to update because it generally keeps the correct time after sleep with no wifi or 3G connection. It doesn't need a separate clock battery because it has a big main battery.This could be related to a timezone issue in the OS software, where its jumping ahead or backwards. As long as the timezone / country is set correctly it should be fine. Also, note the iPad has no separate internal lithium clock battery so this is obviously updated via wireless / 3G connection.