Grant Paul a.k.a chpwn and Ryan Petrich have released a legal working Siri port for older jailbroken iOS devices. The tool known as “Spire” and can be installed freely via Cydia. Its not the first and not prefect but all you need is to get access to an iPhone 4S and your own proxy to get the port working. Is been a month since the first Siri protocol cracked and put in the public.
Grant Paul said on his blog
Spire is my (along with Ryan Petrich) new tool for installing Siri on previously unsupported, but jailbroken, devices. Spire is a small download, but while installing it will download Siri itself (directly from Apple). Spire is available in Cydia right now — go get it! This will use about 100 MB of data, so please connect to Wi-Fi before installing.
Spire legal and free but you still need an iPhone 4S authentication key to enter into Spire’s proxy server address. Using SiriProxy, Siri will function in full capacity on all non-4S hardware. A tutorial on how to install your own SiriProxy can be found here.
However, Spire is not a complete solution. Apple still requires authorization to use Siri, so information from an iPhone 4S is still required. To insert this information, Spire allows you to enter your own proxy server address. By using this (ancient) SiriProxy fork, you can setup a proxy using your own iPhone 4S to insert the needed information reasonably easily. Other solutions for proxying Siri will be listed here as they are developed — perhaps that sort of proxy might be included in the main SiriProxy repository.
Spire uses a new method to obtain the files necessary for Siri, so it doesn’t have the copyright issues encountered by previous attempts. Similarly, rather than directing all traffic through a specific proxy server (and the associated privacy issues), Spire allows you to specify your own proxy server.
Download Spire via this link if you are on a jailbroken iOS 5 devices.