MDAC 2.5 SDK - OLE DB Programmer's Reference
Chapter 1: Overview of OLE DB
OLE DB defines an interface, ITransactionJoin, for consumers to request that providers enlist in a coordinated transaction among multiple (possibly distributed) data providers and other types of resource managers. The details of how providers enlist themselves as resource managers with the transaction coordinator are described in the Component Services (known as Microsoft Transaction Server if you are using Windows NT) documentation.