There's critical bug found in the iOS 4.1 of the iPhone 4, this bug lets you bypass iPhone 4 passcode lock and allows you to make calls and access contact information. There's a simple technique for how to do this, you just have to lock your iPhone with a passcode then press emergency call and type a non existing number (as ###). Next tap the call button and immediately hit the lock button. It should open up the Phone app where you can see all your contacts, call any number, etc.
After your iPhone passcode is unlocked you can make calls, send emails, you can see the entire list of contact, recent call history and voicemails. Well this is an highly crirtical bug in iOS 4.1, it might be a risk for so many people. So, Apple, you have to say something about this and fix it immediately !
Bug no iOS 4.1 from Salomão Filho on Vimeo.