T-Mobile G2 thwarts rooting

T-Mobile's new G2 handset, its latest own-brand Android smartphone and the successor to its popular G1, comes with an unwelcome bonus: a kill-switch that prevents users from installing custom ROMs.

The anti-circumvention mechanism was discovered by ardent mobile hackers over on the XDA-Developers forum, who successfully managed to gain super-user permissions on the Android-based handset and install custom software - only to find that the handset detected what they'd done and forced a re-install of the stock software.

Each time the users installed a custom ROM or gained super-user - known as 'root,' after the user name used for the administrative account on the underlying Linux platform - the T-Mobile G2 resets itself and restores a pristine copy of the OS.

Gaining super-user access to an Android smarphone, a process known as 'rooting' and analogous to 'jailbreaking' an iPhone, allows users to work around restrictions in the platform - such as an inability to use the cordoned-off 'system' portion of the device's internal memory, or to install software that uses unauthorised APIs such as the ability to take screenshots or act as a Wi-Fi to 3G gateway.

It also allows for the installation of fresh version of the operating system - known as ROMs - which remove the T-Mobile branding and quick access to T-Mobile applications, as well as removing any restrictions that the mobile provider may have placed on the handset.

As a result, it's not exactly surprising to see that T-Mobile has made the move to block hackers and tinkerers from gaining administrative access to the device, but it's certainly a disappointment for those who bought the G2 specifically to modify.

Work continues on developing a permanent method of bypassing the protection system built in to the G2, but initial reports indicate that it hinges on a cryptographic signature in the ROM which may be hard to crack for enthusiastic amateurs.

If there's one thing that history shows us, however, it's that this sort of restriction doesn't tend to stop people for long - as Sony is finding out to its cost.