I never heard the domain change of SQL Server in mixed mode. Could you explain a little bit more in detail?
Many thanks in advance.
If you are talking about the change of server name in domain, that is a different story. If you use a default instance, you do not need to change anything. If you use a named instance, please refer to the following links
http://www.ledscripts.com/tech/article/pdf/2
http://support.microsoft.com/kb/319016