As of right now we have not programmed all the commands yet but you can see from this video that it proves this is a google processing server and not apples.
We plan to release a i4Siri package in the main repositories on Cydia that will add on to Spire. This means it will automatically add the server address. From there you will need to go to our client page and signup for an account. The account will allow you to add different UDID numbers for different devices and download the certificate to connect through ssl to our server.
i4Siri can also work on 3G. Spire works on all network interfaces so therefore our server will work as well. The 3GS is supported as well as the iPad 2, iPhone 4, and iPod Touch 4G.
See the Demo Video
We hope that soon we have "Siri" alternative on our iDevices.