You thought you locked your iPhone with a password protection and you are safe? Not really … TUAW.com published a serious iPhone bug in the lock code of iOS 4.1, and seems already settled in the new beta version 4.2 of iOS.
iphone_bug
The ruling is that a person could access the phone application on the iPhone, with access to contacts, bookmarks, voice dialing and voice, and follow-up, editing a contact, access our photo library. You can not go further and made the phone remains locked and does not respond or the start button or the button sleep. The only way to react is to leave the button sleep for more than 5 seconds, and when we see the option off, then again press for that this time it works and the phone returns to normal. Following is the video of proof.
It is certainly a very grave security breach, so you are notified of the problem.