When I heard the headline I thought about the thousands of unsecured VoIP devices which will be running in the country, but it turned out to be one of the oldest tricks in the book- logging into voicemail with no PIN number. Maybe we will start to hear about VoIP hacking in 10 years time.
Of course you need a PIN number on your voicemail account. Not just to prevent this, but to prevent people listening to your voicemail, changing the greeting, changing your auto attendant, etc etc.
I really shouldn't even bring it up, it is such non-news but I just don't know how this still gets past news editors.