MS KB 295765 clearly says:
“The server is a single-domain solution, which is not intended to be integrated with other Windows domains. You are not permitted to establish explicit trusts to other Microsoft Windows NT nor to Active Directory domains. Also, Small Business Server 2000 does not enable you to create child domains.”
Note that the SBS EULA mentions the following:
“1.e Reservation of Rights: Microsoft reserves all rights not expressly granted to you in this EULA”.
In order to comply with this EULA I have removed this page from the site.