ID Fraud Lord Buckingham

BBC and el Reg are running great stories about some guy who read Day of the Jackal and decided to find a dead baby, take his birth certificate, open a bank account, get a passport – and live as this baby for 23 years! Of course, he had to go and take a fictional title (Earl of Buckingham) which hadn’t been in use since 1700 or so.
After getting married, fathering two sons, getting a divorce, this IT consultant was finally caught in 2003 and arrested for travelling under false documentation.

The stories are here:
The Register

Now, the question they fail to answer is: how did they twig on him at all? I’ve read the Day of the Jackal and the way the method works means that the passport he was travelling under was not a forgery…