On the 11th of September 2003 NASK released the domain names with the "xn--" prefix for a registration in .PL zone and on the 18th of September 2003 in the second level domains managed by NASK.
A domain name with the "xn--" prefix must be prepared in accordance with IETFs dokuments i.e. RFC 3490, RFC 3491, RFC 3492 in order to be registered.
The domain name with the "xn--" prefix submitted for registration, after it has been transformed into the unicode form, can include merely code points from one of the sets defined in allowed_character_sets.pdf document. A combination of characters from different sets is not allowed.
A domain name with the "xn--" prefix represented by ASCII code points is registered in accordance with the IDNA standard (RFC 3490). NASK shall not be held responsible for consequences of common adoption of international standard different than standard used on the day of particular domain name registration. If you register a domain name in ASCII code points with the "xn--" prefix you agree to benefit from the service rendered by NASK, subject to a condition mentioned in the previous sentence.
2006 
