If you are using ADMT version 3.2, the source and target domains must be at least at a Windows Server 2003 functional level.

http://technet.microsoft.com/en-us/library/cc974342(WS.10).aspx

 If you are using ADMT version 3.2, the source and target domains must be at least at a Windows Server 2003 functional level.

http://www.microsoft.com/download/en/details.aspx?id=8377