Chpwn and Ryan Petrich released a new Siri port called "Spire" for installing Siri on previously unsupported, but jailbroken devices including: an iPhone 4, iPhone 3GS, third generation iPod touch, fourth generation iPod touch, and first generation iPad.
"Spire is a small download, but while installing it will download Siri itself (directly from Apple). This will use about 100 MB of data, the developers recommend that users connect to a Wi-Fi network before downloading, not a standard cellular network," according to Chpwn blog post.
"Until the iPhone 4S is jailbroken, this is the best Siri port," tweeted Steven Troughton-Smith, "when the iPhone 4S is jailbroken, then we can avoid the proxy server issues."
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.
Chpwn writes "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."
Spire is available in Cydia right now -- go get it!