.it domains, che gioia 
European domains sometimes really are fun. Apart from some European registries insisting on obscure nameserver validations, they are also famous for having registrars who insist on IP addresses, even though they are completely irrelevant and meaningless in this context.
As I wrote a couple of days ago (yet again in the context of a European registrar, incidentally Italian)
The link provided back then is, of course, the same as @fritex posted in his previous response, which was spot-on for this particular endeavor - even if completely pointless as already mentioned 
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Choose any address you like, you can probably even specify 127.0.0.1 
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