I have been asking my Embassy
I have been asking my Embassy, the Italian Embassy in Addis Ababa, what is the procedure to get married with my Ethiopian fiancé but, after 20 (twenty!) days of emails, telephone calls, and a personal visit to the embassy (which was a complete nightmare! more details to come...) I still do not received the correct answer!
Why not putting this information on the website?
I will keep further updates here
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15 days later: still not feasible solution from the Italian consulate: we opted for the "consulate marriage" (esteri.it - "Application to get married in a Consulate") as stated in the official website of the Italian Minister of Foreign Affair: the Italian consulate confirmed that it is possible, but we have then been asking the application form to the consulate since the 27th of April, and still no answer.
Once again: why that application form is not online?
Update: we finally made it to be married in the consulate, but it was really a pain: it took almost 4 months of email/phone calls/stress, and at the end we have no idea why the whole process was painful for us, and apparently for the consulate, too (they ended up being pretty angry at us for the hassle we've caused).
We are pretty sure something has gone wrong in the whole process, and have no idea what it was: anyhow we are finally married.