Private information stored in Apple's iPhone and protected by a lock code can be accessed by anyone with just a few button presses.

Read our Apple iPhone 3G review and Apple iPhone 2.0 software review

Like most mobile phones, the iPhone can be locked with a four-digit code. However unlike other phones, which in their locked state only permit calls to emergency service numbers such as 999, a locked iPhone can be used to make a call to any number.

However, that's not all you can do with a locked iPhone running the latest version of Apple's software, 2.0.2.

Pressing the emergency call button at the unlock screen, followed by two taps on the home button, takes you to the iPhone's private 'Favorites' page without the need to enter the unlock code. If the owner of the phone has favourite entries in their address book containing URLs, email addresses or mobile phone numbers, then those entries can be used to launch the browser, mail application or SMS software and gain access to private web favorites, email messages and text messages stored in the phone, again without entering the unlock code.

The security flaw, revealed by a member of the forum, came as a surprise to an Apple spokeswoman, who said she would look into the matter.

One way to avoid such unauthorised access to email messages or web favorites would be not to add email addresses or URLs to favorite address book entries.

Apple pushed version 2.0 of its iPhone software as being more enterprise-friendly: some businesses had been reluctant to adopt the first version of the iPhone because it did not adequately protect corporate information stored in the device.