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I wrote a very long reply trying to solve this mystery but the board ate it up. :eek:

This is probably just the shipping firmware for the CDMA iPhone 4. Nice find!
 
Kinda sounds like it's legit. The dev-team guys are twittering about it.
 
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ulbador said:
Kinda sounds like it's legit. The dev-team guys are twittering about it.

The fact that the file is on the official Apple download server further reinforces the legitimacy of the firmware ;)
 
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