The software in the Apple iPhone flaw, er four, has a bug which allows a person to pick up a locked phone and make a call.
According to a film being seen on YouTube
there is a bug in iOS 4.1 that allow users to bypass the device’s lock screen and make phone calls. All you have to do is press the “Emergency Call” button, dial a non-emergency number (such as “###”), then quickly press “Send” followed by the iPhone’s lock key.
This will force the device into the “Phone” application. From there you can access the person's favorites, contacts, the dial pad, recent calls, and voicemails. You cannot jump to the home screen, but if you go to the “contacts” tab, selecting a contact, and clicking “Email” or “Share contact” you can send emails and MMS messages. (As if anyone ever sends MMS messages. sub.ed.)