Phone Hacking

Amidst the welter of mainstream news regarding phone hacking and dodgy behaviour by the British press I chip with a certain reluctance. Phone hacking suggests some technology wizardry and invokes some imagery of a bored but brilliant teanager exercising huge technical skill. In fact 'caller ID spoofing,' the technique probably used here, is relatively simple and involves calling the voice mail message centre from a phone with a caller ID that appears to be the same as the number of the victims phone.

Caller ID is the feature that allows you to see who an incoming call is coming from.  A number of companies exist which offer a caller ID spoofing service. To use a Caller ID spoofing service, customers pay in advance for a PIN, allowing them to make a call for a certain amount of time. Customers dial the number given to them by the company and enter their PIN. Then they enter the number they wish to call.
https://www.telespoof.com/
To access someone else's voicemail, which happened in the Dowler case, the number to call is the number of the voicemail service of the victims cellphone service provider. They must enter the number they wish to appear as the Caller ID as the number of the victims phone. When the call connects to the voicemail service the system uses the caller ID number to connect the call to the correct mailbox. Sometimes a PIN code will be also needed but these are often not used or will be 0000 or 1234 or some other easily guessed number. 
Then, when the hacker is into the voicemail system 'as the victim', can he replay or even delete the victims messages. 
Caller_ID_spoofing - Wiki
http://www.wired.com/threatlevel/2006/08/paris_hilton_ma/
The fact that this was happening became obvious to Britain's Prince William when he got onto his own voicemail and discovered messages tagged as SAVED MESSAGES that he'd not heard before. Someone else had been into his voice mail and replayed them first, while they were still NEW MESSAGES. This ought to be something of a give away for even the slowest Inspector Plod but even where Royal security was concerned the police have been reluctant to persue the matter.
In the case of the murdered school girl, Milly Dowler, her voice mail message was hacked into repeatedly and the messages of family and friends, desperate to get in contact with her, became news. The individuals involved in hacking were perhaps being paid on a message by message basis and finally when the voice mail was full and no new messages could be stored the hackers took it upon themselves to delete old messages to make room for new ones. By this stage not even Plod of the Yard could ignore the fact that unathorised people were accessing private messages and interfering with a murder investigation. 
Now, it seems, this 'revelation' has brought down one of Britains oldest popular tabloids. Big deal, there's plenty more bildzeitung keen to take over from the NOTW. Rebecca Brooks, CEO of the NOTW, is still claiming to have known nothing about it. Journalist on the NOTW claim that even the office cat knew about the phone hacking. What a disaster, and what a piss poor show by the police.