In the "Orcas" March 2007 CTP for Visual Studio and .Net, Windows Communication Foundation brings support for OASIS specifications WS-AtomicTransaction 1.1 and WS-Coordination 1.1. WCF will have side-by-side support with the 1.0 versions of these specs.

To use the new version of WS-AT, you can specify the new WS2007HttpBinding, or, if you already use the NetTcpBinding, you can set the TransactionProtocol to WSAtomicTransactions11.