Yes, it is. However, I'm investigating whether installing some utilities from the site below will help. They indicate that they're backward compatible, and will enable my SS 2000 install to talk cleanly to SS2008R2.

(I wish my clients would upgrade!)

Thanks for responding! I'll post results of my experiments when able.

http://www.microsoft.com/downloads/en/details.aspx?FamilyID=1b2bd555-cb5b-47b9-88c7-3f89f3b43779