Microsoft Knowledge Base Article 812453 contains the following summary:

Under certain conditions, you may have to move a computer that is running Microsoft Exchange 2000 Server or Microsoft Exchange Server 2003 Server from its current domain to a new domain. However, moving a computer that is running Exchange 2000 or Exchange 2003 from one domain to another is not supported. Additionally, running the /disasterrecovery Setup command against the Exchange computer object that was previously in a different domain is not supported.