Sam Ruby points to WS-Transaction. But look at the list of authors. The problem is IBM and Microsoft have a lot to preserve by maintaining more or less traditional databases and transaction protocols.
I've written an essay on what I think the next database architectures should look like. If you read through my blogs you'll know it has something to do with tuple spaces and star schemas. But Jon goes on to ask, "How do you preserve the fluidity that the agile enterprise requires?" There is a little bit more to say, since enterprises are not nearly as agile as they need to be.
WS-Transaction is intended to preserve the status quo rather than improve agility. I'll publish more on this in the near future.