Locked iPhones still got their ears on
It's a feature, not a bug
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The iPhone passcode has never been particularly secure, but now it seems that a locked handset will respond to a good talking-to, unless the user remembers to opt out.
iPhones locked with a passcode PIN, which should prevent thieves and prankster friends from operating the phone, can still be used to make calls thanks to a default setting that keeps voice dialling in operation. That means anyone can pick up an iPhone, hold down the home key and make calls to their heart's content, or to the handset's ability to recognise their voice.
The option can be switched off in the settings, and, just like the last hole in the iPhone passcode system, this has gone unnoticed for a while before being brought to our attention by a couple of sharp eyed El Reg readers*.

It's not a huge deal, and one imagines the decision to enable the function by default has to do with peripheral connectivity - so Bluetooth headsets and the like can use voice dialling when the screen is locked.
Apple is maintaining its traditional silence on the matter so we can't be sure, but if you don't generally use voice dialling then it's probably worth diving into the settings and tabbing it off. ®
* With thanks to Iain and Chris for their note on the subject.
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COMMENTS
depends on where you are
If you were in the UK you would probably be arrested as a terrorist suspect. Or shot. Depends on your accent too.
Indeed...
A truly locked phone would be pretty hard to return to the owner unless the owner realised the phone was lost and called it before the 24 hours of operation the average super smart phone can manage had expired.
I did find an N95 8gig a few years ago in a pub. Luckily it wasn't locked, so I called the last two people the owner had called and explained the situation. One of the people was a work mate who would be seeing the owner next morning, so I left my number so they could call me.
A few days later the phone was back with its owner, and I earnt a couple of free beers after work, which is always nice.
"...thieves and prankster friends..."
Mobe security systems need to include consideration of the fact that many people that may discover a lost phone are perfectly honest, and they'd just like to return it to the rightful owner as quickly and simply as possible. The overall security, locking, Find-My-Iphone scheme should include a facility that allows the honest finder to make contact with the owner (obviously via some means other than their phone). If the only interface is just a passcode lock screen, it isn't exactly making it easy for the finder.
When my son's Ipod Touch was 'borrowed', the screen lock passcode prevented the 'borrower' from connecting to his wifi hotspot, which prevented the Ipod from connecting to the Internet, which prevented the Find-My-Iphone (Me.com) feature from working. Not an issue with Iphones, but still an indication that the overall scheme hasn't really been fully sorted. Borrower was forced by his parents to return the 'borrwed' Ipod back to school.

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