Looks like good ole social engineering was behind the oh sooo publicized T-mobile sidekick hack of Ms. Hilton.

Computer security flaws played a role in the attack, which exploited a programming glitch in the Web site of Hilton's cell phone provider, Bellevue, Wash.-based T-Mobile International. But one young hacker who claimed to have been involved in the data theft said the crime only succeeded after one member of a small group of hackers tricked a T-Mobile employee into divulging information that only employees are supposed to know.

The young hacker described the exploit during online text conversations with a washingtonpost.com reporter and provided other evidence supporting his account, including screen shots of what he said were internal T-Mobile computer network pages. Washingtonpost.com is not revealing the hacker's identity because he is a juvenile crime suspect and because he communicated with the reporter on the condition that he not be identified either directly or through his online alias.
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In the months leading up to the Hilton incident, the hacker group freely exploited a security glitch in the Web site of wireless phone giant T-Mobile, according to the hacker, who described himself as the youngest member of the group. The group had found that a tool on the T-Mobile site that allowed users to reset their account passwords contained a key programming flaw.

By exploiting the flaw, the group's members were able to gain access to the account of any T-Mobile subscriber who used a "Sidekick," a pricey phone-organizer-camera combination device that stores videos, photos and other data on T-Mobile's central computer servers.

] When hotel heiress Paris Hilton found out in February
] that her high-tech wireless phone had been taken over by
] hackers, many assumed that only a technical mastermind
] could have pulled off such a feat. But as it turns out, a
] hacker involved in the privacy breach said, the Hilton
] saga began on a decidedly low-tech note -- with a simple
] phone call.