Jailbreaking is like "sneaking through the door into someone's data center," Hoffman says. "Once inside, there are typically less protections than there are outside, which allows you to then do other things which will ultimately grant you root access or, as in the case of a WP7 phone, perform activities as though you were a system administrator."

Both jailbreaking and root access for Windows Phone 7 are inevitable, Hoffman predicts.

Asked to comment on Walsh's exploit, Microsoft issued the following statement: "We anticipated that people would attempt to unlock the phones and explore the underlying operating system. We encourage people to use their Windows Phone as supplied by the manufacturer to ensure the best possible user experience. Attempting to unlock a device could void the warranty, disable phone functionality, interrupt access to Windows Phone 7 services or render the phone permanently unusable."

John Cox covers wireless networking and mobile computing for Network World. 

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