It appears that Apple is well known from the rising rumors of Siri port on older iOS devices even on iPhone 4. The latest rumor suggests that Apple has been testing Siri on iPhone 4 with special builds of iOS 5 firmware to it’s a number of employees. The news doesn’t confirm that we will surely get the Siri for iPhone 4, but at least informs to some nasty users who want Siri on their iPhone 4.
No Siri For iPhone 4
It seems that Apple has no plan to release Siri for the older devices, and therefore, they already opted to send out the couple of emails to their developers, letting them know that there will be no Siri for older devices, at least at this time or in a near future. Apple has just confirmed its upcoming plan through the bug fixing email to developer, Michael Steebar. The email slightly confirms that there will be no Siri for iPhone 4/iPad 2 in the near future.

Engineering has provided the following feedback regarding this issue: Siri only works on iPhone 4S and we currently have no plans to support older devices.

On the other hand, iPhone Jailbreak Hackers also announces that they will not release the Siri port to older devices in public because the Siri is strictly baked for iPhone 4S and the port requires some of the iPhone 4S core and firmware files, which are not publicly available for all users and requires a bit of Apple Software Piracy. Well at the moment, no one is here to provide you Siri legally on your iPhone 4 or iPad 2. It’s quite better to forget about the port and move on to some next amazing feature of the device.