If you are an Epic 4G user odds are you were rather excited when the 2.2.1 update began to roll out for your device. And as you know, it was pulled due to some ... issues. And one of them appears to be with the lock screen and inbound phone calls, and the vulnerability the device has when receiving a phone call. Users have noticed that if they have a password on their device, thinking that it is safe from others getting into it, that if the device receives an inbound phone call and you accept, if you quickly press the home button a few times you are into the phone, with access to all the information.
While yes, you would need to have the phone number associated with the device, it is still a huge potential flaw for keeping anyone who knows you out of your device. Users have reported that once the call is ended, the device becomes locked again, which is a good thing, but still scary that they can be using your calling minutes, and searching all your personal information at the same time. [Android Central Forums, Bug list]