AnyVoice is a jailbreak tweak that allows you to fit Siri with nearly 40 different accents from around the world is now available for download in Cydia.

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AnyVoice is available for a free from Cydias ModMyi repo. You will need a jailbroken iOS 5 install with Siri (either legit iPhone 4S Siri or Spire) to take advantage of AnyVoice.