A hacker group has successfully ported Siri over to jailbroken iPhone 4's and 4th-gen iPod touches, marking the beginning of what could be a "whack a mole" response from Apple as it attempts to block the 4S's "killer feature."

The crack comes courtesy Steve Troughton-Smith and Grant Paul, who published their achievement via the Twitters, complete with screenshots (9to5Mac interviewed the pair last night with additional details).

According to Troughton-Smith, the hack was created with a single line of code and a barrage of filesystem changes. Details of the hack are forthcoming, he said, once it's confirmed to work with the iPhone 4 and iPod touch in such a way that does break everything in a spectacular fashion. No release date for the Siri hack was given.

That Apple has probably taken note of this (even in private) is an understatement—the voice-activated Siri is at the center of the current iPhone 4S marketing campaign. This "exclusive" feature appears to be anything but. [AppleInsider]