Fresh from having to apologise for security breaches within the iPad's email function, AT&T is facing more pressure as it appears the company has well and truly messed up on the security front again - this time with iPhone 4 pre-order customers' data.

Gizmodo is reporting that at least three of its readers have faced the scenario whereby they have attempted to log in to their AT&T account to order the next-gen iPhone, only to be re-directed to another customer's account details.

Now, there is obviously some very private data within a users account, although AT&T has denied to Gizmodo that this data would include call records and credit card numbers. Still, we wouldn't fancy any Tom, Dick or Harry getting hold of our address, email and other contact details.

Gizmodo has spoken to an AT&T insider who claims the security breach could go even deeper though. He claims that a major update took place on the AT&T systems over  the weekend, that ultimately went wrong and that there was "no testing of this system done before the launch of the new iPhone".

Fishy business indeed, and with AT&T already under pressure following reports of poor 3G coverage for the iPhone and the iPad security flaws, the errors could not have come at a worse time.

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