"In a pretty sizable and scary (and weird!) security bug, Apple's Smart Cover can be used to unlock any iPad 2, even if there's a passcode on it. Here's how it works. And here's how to fix it."
The first thing that always goes through my mind when stuff like this pops up is "what in the world made them think to try this?" Basically the fix is to turn off the Smart Cover unlocking in the General Settings menu until Apple can issue a fix. Or just hang on to your iPad 2 and not worry about it.
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iPhone 4, 1.6 GHz Core 2 Duo MacBook Air, Apple TV, 2.66GHz Intel C2D Mac Mini, 1TB TC, Airport Extreme,several iPods and an iPad, 32GB Wi-Fi version. Follow me on Twitter.