A question I get asked every now and then that doesn't seem to be particularly well documented is whether SMS 2003 supports renaming of the domain or domain migration.  While technically two different things, the short answer is no, we do not support changing the domain name that SMS 2003 is installed into.

Page 235 of the Scenarios and Procedures for Microsoft Systems Management Server 2003: Planning and Deployment doc says:

Caution:
To change the domain name and the computer name after SMS is installed, you must remove your installation of SMS, change the names, and then reinstall SMS. To avoid this time-consuming task, consider this information carefully before you enter it.

For the long answer, see the notes below:

• If SMS primary or secondary sites exist in the domain that is being renamed, SMS will have to be uninstalled and then reinstalled with the new domain name. You will not be able to restore the existing SMS database after reinstallation - you will have to start with a clean database.
• If the domain being renamed is part of an SMS site but has no primary or secondary sites located in it (only logon servers and clients), the domain should be removed from the site prior to the name change and added back into the site after the change.
• If you are running Internet Information Server, you might need to change the account specified in virtual paths. 

SMS client and SMS sever components pass only NetBIOS names to the operating system for resolution. SMS never uses fully qualified domain names. If a computer’s common name is the same as its NetBIOS name, and DNS is configured appropriately, you can manually resolve the common name to an IP address with the Net Use command. In this case, SMS will operate properly without WINS.

Hope this helps,

J.C. Hornbeck | Manageability Knowledge Engineer