http://www.rfc-editor.org/rfc/rfc5564.txt
RFC 5564: Linguistic Guidelines for the Use of the Arabic Language in Internet Domains, A. El-Sherbiny, M. Farah, I. Oueichek, A. Al-Zoman2010-02-01T23:00:00-00:00This document constitutes technical specifications for the use of Arabic in Internet domain names and provides linguistic guidelines for Arabic domain names. It addresses Arabic-specific linguistic issues pertaining to the use of Arabic language in domain names. This document is not an Internet Standards Track specification; it is published for informational purposes.