Well that's bad news: The Register is reporting that it's possible to send a malicious MMS to Windows Mobile phones (at least Pocket PC 2003 and Smartphone 2003 phones) that could possibly infect them with malicious code. More likely it would just crash the phone (thank god for small favors), though, as it's apparently wicked-tough to implement.
All in all, we've had a remarkably long honeymoon when it comes to security on mobile devices. Hopefully it's not over yet.
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