NIC Argentina has recently advised registrars IDNs will be available for registration starting sometime before August 2008). The Argentinean IDN launch will comprise four stages:

1. 30 day Awareness campaign, after which there will be a
2. 100 day Sunrise for holders of equivalent non-IDN domain names (only domains registered before this announcement), after which there will be a
3. 90 day Assignment period for domains requested during the Sunrise. (in case a domain name is applied by more than one party, the application by the holder of the oldest equivalent non-IDN domain will prevail), after which there will be a
4. IDN Landrush open to anybody with an official postal address in Argentina. (If your client does not have their own local Whois presence in Argentina, a registrar such as LatinTLD can supply it).

In the Sunrise period, the following conversions will apply, enabling holders of non-IDN domains to apply for their IDN Spanish and/or Portuguese equivalent domain names:
(I ) “a” =>”á”, “â”, “ã” o “à”.
(II ) “e” =>”é” o “ê”.
(III) “i” => “í”.
(IV ) “o” => “ó”, “ô” u “õ”.
(V ) “u” => “ú” o “ü”.
(VI ) “n”, “nh”, “ni”, “nn”, “ny”, “gn” => “ñ”.
(VII) “c” o “s” => “ç”.

To register your .ar domain names, check out America Registry here.