Scary stuff, yet the enterprise security community seems strangely quiet on the topic, aside from showing other journalists how easy it is to do.
Potentially, if you know the correct mobile number and you can guess 4 Digits, you too can be listening to your elected leaders personal messages. The chances are pretty good that it could be their birthday.
Does your security policy take the carrier into consideration? Does your security policy make a point of your users changing the default PIN?"