We've seen an unreleased Siri hack that purportedly works on the iPhone 4, and now there's a jailbreak package cheekily dubbed Siri0us that uses a workaround to bring Siri dictation to jailbroken iOS 5 devices (it's been confirmed to work on the iPhone 4, iPhone 3GS, and iPod Touch). Like Siri, the hack is powered by Nuance's voice recognition technology and is able to replace the keyboard within apps, but there are important differences. Since phones other than the 4S can't communicate with Apple's Siri servers, Siri0us appears to use Nuance's API (without permission) to connect to the servers that the speech recognition company hosts for apps such as Dragon Go instead. This workaround means that the hack is unable to use the server-based Siri AI, which aids Siri voice recognition to some extent. By all accounts, it appears that this hack works pretty well within the search and Note apps, but we don't expect it to be around for long, unless developer Eric Day somehow gets permission to use Nuance's API. Try out Siri0us while it's still available by downloading it through Cydia, and check out a video of it in action below.