Microsoft's Metadata Management

The metadata services is part of MS SQL Server 2000.

http://www.microsoft.com/sql/techinfo/BI/mds.asp

Their model management techonology uses an algorithm called CUPID to map two data sources together. It was developed by Phil Bernstein. The paper goes through the various different way to match two different models (or database/xml schemas) using linguistic, element, structure, referential and contextual matching.

http://research.microsoft.com/db/ModelMgt/
http://research.microsoft.com/~philbe/

CUPID paper:
http://research.microsoft.com/db/ModelMgt/CupidVLDB01.pdf

Another such tool is ARTEMIS here's a paper called: "A Schema Analysis and Reconciliation Tool Environment for Heterogeneous Databases":
http://www.computer.org/proceedings/ideas/0265/02650053abs.htm

The MOMIS Project is the parent project:
http://www.dbgroup.unimo.it/Momis/