Thank you so much mat0pad!!!
I have tried your way and it doesn't crash my game either on the iOS simulator and on my actual ipad.
It also returns correctly IT for Italy, when the device is connected to internet.
It could potentially fix my problem for now...
Unfortunately I can not actually use this behavior because I can not have this "IT" actually stored in a game attribute.
I have written: if Language=IT set GameAttributeLanguage to it , but it seems the game does not actually sett the game attribute to the value "it" and it keeps the default value "eng".
The behavior using "nme.system.Capabilities.language" crashes on iOS simulator in 95% of tests, but not always, which is also quite strange, while on my real ipad it works ever and fine. Deactivating the part of behavior where the code is avoids the crash in 100% of the tests.
I am starting to think my game has problems related to game attributes and these problems do not depend on my behavior. I have other strange crashes probably depending by behaviors not actually executed in my game.