Months ago when Apple released iPhone 4S, it was assumed that Siri would come to devices other iPhone 4S. But the fact remained true that Apple has no plans in the future to bring it to iPhone 4 and iPhone 3GS. Even if it is possible unofficially, the method was supposed to be completely illegal until Apple seeded iOS 5.0.1 with non-encrypted system files. Spire via Cydia has been released from Chpwn which brings Siri port in other devices legally.
Spire appears to be a small sized download. Once you have downloaded, it would fetch all required Siri files directly from Apple which are 100MB+. However, this is not the end. You still need something to make it completely work. Due to the fact that you got all files legally, you need a proxy server from an iPhone 4S owner or from a friend for the full functionality. Chpwn has guided on how you can use a proxy server on the tweak itself. All you need is the authentication from an iPhone 4S owner.
The only reason is the privacy issues which could occur once one specific proxy server is provided. Anyone around the world could access your confidential data from your iPhone, also called unauthorized access. Just to name a few, you would be risking your Email, SMS, Calendar, Contacts, Location, etc through that server. Needless to say, people would start selling Siri proxy in future. Though, nothing has come into scene till now. It could be one of the way for people to use Siri.
Until today, there’s no way with which one could spoof Apple sever without proxy. For Chpwn, it seems impossible to solve the issue and people might resolve it in coming months. Nevertheless, this is the best he could do. Have you tried it yet? Let’s know in the comment section.