The one feature that really, truly distinguishes the iPhone 4S from its predecessor, the iPhone 4, is the digital-assistant software Siri. To this point, it’s been possible--but illegal --to shoehorn the helpful program onto the older phone.

With Apple’s latest update, however, Cult of Mac reports that home hackers will be able to pull the files for a Siri port without running afoul of Apple’s copyright.

In the past, those looking to put the program on anything that wasn’t an iPhone 4S had to resort to methods such as illegally tricking Apple’s servers into recognizing their older devices as the latest handset. Now, the report says, thanks to the iOS 5.0.1 update that Apple pushed out on Thursday, the files that operate Siri are wide open.

News of this possibility was first tweeted by a prominent hacker who is part of a group that makes software for jailbroken iPhones.

Cult of Mac says it’s not clear why, exactly, the files have been suddenly made accessible, and notes that it’s possible that Apple will put up its walls again in its next software update.

But, for now, the doors are open to the hacking community to make Siri on older Apple devices a legal possibility.

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