Invalid nameserver hostname

REG-FO@localhost> create_nsset NS433 ((NS1.DOTSERV.NET), (NS2.DOTSERV.NET)) ID002103 Do you really want to send this command to the server? (y/N): y Return code: 2005 Reason: Parameter value syntax error ERROR: Element that caused a server error condition: <nsset:name xmlns:nsset='http://www.nic.cz/xml/epp/nsset-1.2'>NS1.DOTSERV.NET</nsset:name> Reason: Invalid nameserver hostname. Element that caused a server error condition: <nsset:name xmlns:nsset='http://www.nic.cz/xml/epp/nsset-1.2'>NS2.DOTSERV.NET</nsset:name> Reason: Invalid nameserver hostname. Why do i get this error ? Do i need to specify wich countries are allowed for nameservers ? If yes, how do i do that ? regards Petur This email and its attachments may be confidential and are intended solely for the use of the individual to whom it is addressed. If you are not the intended recipient or authorized to receive information for the intended recipient you are notified that disclosing, copying, distributing or taking any action in reliance on the contents of this information is strictly prohibited. If the email contains proposals, they are valid for 30 days following the date of email transmission. Finally, the recipient should check this email and any attachment for the presence of viruses. The company accepts no liability for any damage caused by any virus transmitted by email.